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question:A thirsty traveler who weighs 160 pounds found an oasis in the desert. He drank water equivalent to 0.5% of his body weight. His camel, which weighs 1200 pounds, drank water equivalent to 2% of its body weight. There are 128 ounces in a gallon. How many gallons of water did they drink altogether?
answer:First, I need to determine how much water the traveler drank. The traveler weighs 160 pounds and drank water equivalent to 0.5% of his body weight. To find this amount, I'll calculate 0.5% of 160 pounds.Next, I'll calculate how much water the camel drank. The camel weighs 1200 pounds and drank water equivalent to 2% of its body weight. I'll find 2% of 1200 pounds.After finding the amounts in pounds, I'll convert them to ounces since there are 16 ounces in a pound. This will give me the total ounces of water consumed by both the traveler and the camel.Finally, I'll convert the total ounces to gallons using the conversion factor of 128 ounces per gallon to determine the total gallons of water they drank altogether.
question:Lucky Lila is asked by her teacher to substitute numbers for a, b, c, d, e, and f in the expression acdot(b-(ccdot(d-(e/f)))) and evaluate the result. Lila ignored the parentheses but multiplied and divided correctly and obtained the correct result by coincidence. The number Lila substituted for a, b, c, and d were 2, 3, 4, and 5, respectively. What value did Lila substitute for e if she substituted 6 for f?textbf{(A)} -2 qquad textbf{(B)} -frac{51}{28} qquad textbf{(C)} 0 qquad textbf{(D)} frac{51}{28} qquad textbf{(E)} 2
answer:Okay, so I have this problem where Lucky Lila is supposed to substitute numbers into this expression: a·(b - (c·(d - (e/f)))). But she ignored the parentheses and just multiplied and divided everything in order, and somehow got the correct result by coincidence. The values she used for a, b, c, and d are 2, 3, 4, and 5 respectively, and she used 6 for f. I need to find what value she used for e.First, let me understand the problem. The original expression is a·(b - (c·(d - (e/f)))). So, with the parentheses, the operations are nested, meaning we have to do the innermost parentheses first and work our way out. But Lila ignored the parentheses, so she just multiplied and divided from left to right. Despite this mistake, she somehow got the correct answer. So, both the correct expression and her incorrect method gave the same result. I need to find the value of e that makes this happen.Let me write down the correct expression with the given values. a is 2, b is 3, c is 4, d is 5, f is 6, and e is what we need to find. So, substituting these into the correct expression:Correct expression:2 · (3 - (4 · (5 - (e/6))))Now, let me compute this step by step. First, compute the innermost parentheses: (e/6). Then subtract that from 5: 5 - (e/6). Multiply that result by 4: 4 · (5 - (e/6)). Then subtract that from 3: 3 - [4 · (5 - (e/6))]. Finally, multiply by 2: 2 · [3 - 4 · (5 - (e/6))].Now, let me compute Lila's incorrect method. She ignored the parentheses, so she just multiplied and divided from left to right. The expression she evaluated is:Incorrect expression:2 · 3 · 4 · 5 · e / 6Let me compute this step by step as well. Multiply 2 · 3 first, which is 6. Then multiply by 4: 6 · 4 = 24. Then multiply by 5: 24 · 5 = 120. Then multiply by e: 120 · e. Finally, divide by 6: (120 · e) / 6 = 20 · e.So, according to Lila's incorrect method, the result is 20e.But the problem states that both the correct and incorrect methods gave the same result. Therefore, the correct expression must equal 20e. So, I can set up the equation:2 · (3 - 4 · (5 - (e/6))) = 20eNow, I need to solve this equation for e. Let me do this step by step.First, let me simplify the left side of the equation:Start with the innermost parentheses:5 - (e/6)Then, multiply that by 4:4 · (5 - (e/6)) = 4·5 - 4·(e/6) = 20 - (4e/6) = 20 - (2e/3)Next, subtract this result from 3:3 - [20 - (2e/3)] = 3 - 20 + (2e/3) = -17 + (2e/3)Then, multiply by 2:2 · (-17 + (2e/3)) = -34 + (4e/3)So, the left side simplifies to -34 + (4e/3). The equation is now:-34 + (4e/3) = 20eNow, I need to solve for e. Let me get all terms involving e on one side and constants on the other.First, subtract (4e/3) from both sides:-34 = 20e - (4e/3)To combine the terms on the right side, I need a common denominator. 20e is the same as (60e/3). So:-34 = (60e/3 - 4e/3) = (56e/3)Now, multiply both sides by 3 to eliminate the denominator:-34 · 3 = 56e-102 = 56eNow, divide both sides by 56:e = -102 / 56Simplify this fraction by dividing numerator and denominator by 2:e = -51 / 28So, the value of e that Lila substituted is -51/28.Let me double-check my calculations to make sure I didn't make any mistakes.Starting with the correct expression:2 · (3 - 4 · (5 - (e/6)))Compute innermost parentheses: 5 - (e/6)Multiply by 4: 4·5 - 4·(e/6) = 20 - (2e/3)Subtract from 3: 3 - 20 + (2e/3) = -17 + (2e/3)Multiply by 2: 2·(-17) + 2·(2e/3) = -34 + (4e/3)Set equal to Lila's result: -34 + (4e/3) = 20eSubtract (4e/3): -34 = 20e - (4e/3)Convert 20e to thirds: 60e/3 - 4e/3 = 56e/3So, -34 = 56e/3Multiply both sides by 3: -102 = 56eDivide by 56: e = -102/56 = -51/28Yes, that seems correct. So, the answer is -51/28, which is option B.
question:Given a sequence {a_{n}} such that a_{4}+a_{7}=2, a_{5}a_{6}=-8. If {a_{n}} is an arithmetic progression, then a_{1}a_{10}=____; if {a_{n}} is a geometric progression, then a_{1}+a_{10}=____.
answer:Okay, so I've got this problem here about a sequence {a_n} where a_4 + a_7 equals 2, and a_5 times a_6 equals -8. I need to figure out two things: if the sequence is an arithmetic progression, what is a_1 times a_10? And if it's a geometric progression, what is a_1 plus a_10? Hmm, okay, let's take this step by step.First, let's tackle the arithmetic progression part. I remember that in an arithmetic progression, each term is the previous term plus a common difference, d. So, the nth term can be written as a_n = a_1 + (n-1)d. Given that, let's write out the terms a_4, a_5, a_6, and a_7 in terms of a_1 and d.a_4 = a_1 + 3d a_5 = a_1 + 4d a_6 = a_1 + 5d a_7 = a_1 + 6dWe know that a_4 + a_7 = 2. Plugging in the expressions:(a_1 + 3d) + (a_1 + 6d) = 2 Simplify that: 2a_1 + 9d = 2 Let me write that as equation (1): 2a_1 + 9d = 2We also know that a_5 * a_6 = -8. Plugging in those expressions:(a_1 + 4d)(a_1 + 5d) = -8 Let me expand that: (a_1)^2 + 9a_1d + 20d^2 = -8 Hmm, that's a quadratic in terms of a_1 and d. Maybe I can express a_1 from equation (1) in terms of d and substitute here.From equation (1): 2a_1 + 9d = 2 So, 2a_1 = 2 - 9d Therefore, a_1 = (2 - 9d)/2Let me substitute this into the quadratic equation:[(2 - 9d)/2]^2 + 9*(2 - 9d)/2 * d + 20d^2 = -8Okay, this looks a bit messy, but let's compute each term step by step.First term: [(2 - 9d)/2]^2 = (4 - 36d + 81d^2)/4 = (81d^2 - 36d + 4)/4Second term: 9*(2 - 9d)/2 * d = 9d*(2 - 9d)/2 = (18d - 81d^2)/2Third term: 20d^2So, putting it all together:(81d^2 - 36d + 4)/4 + (18d - 81d^2)/2 + 20d^2 = -8Let me get a common denominator for all terms, which is 4.First term is already over 4: (81d^2 - 36d + 4)/4Second term: (18d - 81d^2)/2 = (36d - 162d^2)/4Third term: 20d^2 = 80d^2/4So, combining all terms:(81d^2 - 36d + 4) + (36d - 162d^2) + 80d^2 all over 4 equals -8.Simplify the numerator:81d^2 - 36d + 4 + 36d - 162d^2 + 80d^2Combine like terms:d^2 terms: 81d^2 - 162d^2 + 80d^2 = (81 - 162 + 80)d^2 = (-1)d^2d terms: -36d + 36d = 0dConstants: +4So numerator is: -d^2 + 4Therefore, equation becomes:(-d^2 + 4)/4 = -8Multiply both sides by 4:-d^2 + 4 = -32Subtract 4 from both sides:-d^2 = -36Multiply both sides by -1:d^2 = 36So, d = 6 or d = -6Now, let's find a_1 for each case.Case 1: d = 6From equation (1): 2a_1 + 9*6 = 2 2a_1 + 54 = 2 2a_1 = 2 - 54 2a_1 = -52 a_1 = -26Case 2: d = -6From equation (1): 2a_1 + 9*(-6) = 2 2a_1 - 54 = 2 2a_1 = 2 + 54 2a_1 = 56 a_1 = 28Now, we need to find a_1 * a_10 for each case.First, let's find a_10 in each case.Case 1: a_1 = -26, d = 6 a_10 = a_1 + 9d = -26 + 9*6 = -26 + 54 = 28 So, a_1 * a_10 = (-26) * 28 = -728Case 2: a_1 = 28, d = -6 a_10 = a_1 + 9d = 28 + 9*(-6) = 28 - 54 = -26 So, a_1 * a_10 = 28 * (-26) = -728So, in both cases, a_1 * a_10 is -728.Alright, that's the arithmetic progression part done. Now, moving on to the geometric progression case.In a geometric progression, each term is the previous term multiplied by a common ratio, r. So, the nth term is a_n = a_1 * r^(n-1).Given that, let's write out the terms a_4, a_5, a_6, and a_7 in terms of a_1 and r.a_4 = a_1 * r^3 a_5 = a_1 * r^4 a_6 = a_1 * r^5 a_7 = a_1 * r^6We know that a_4 + a_7 = 2. So:a_1 * r^3 + a_1 * r^6 = 2 Factor out a_1 * r^3: a_1 * r^3 (1 + r^3) = 2 Let me write that as equation (2): a_1 * r^3 (1 + r^3) = 2We also know that a_5 * a_6 = -8. So:(a_1 * r^4) * (a_1 * r^5) = -8 Which simplifies to: a_1^2 * r^9 = -8 Let me write that as equation (3): a_1^2 * r^9 = -8Hmm, okay. So, we have two equations:Equation (2): a_1 * r^3 (1 + r^3) = 2 Equation (3): a_1^2 * r^9 = -8I need to solve for a_1 and r. Let me see if I can express a_1 from equation (2) and substitute into equation (3).From equation (2): a_1 = 2 / [r^3 (1 + r^3)]Plugging this into equation (3):(2 / [r^3 (1 + r^3)])^2 * r^9 = -8Simplify this:(4 / [r^6 (1 + r^3)^2]) * r^9 = -8 Simplify the r terms: r^9 / r^6 = r^3 So, 4 * r^3 / (1 + r^3)^2 = -8Multiply both sides by (1 + r^3)^2:4r^3 = -8(1 + r^3)^2Divide both sides by 4:r^3 = -2(1 + r^3)^2Let me expand the right side:r^3 = -2(1 + 2r^3 + r^6) r^3 = -2 - 4r^3 - 2r^6Bring all terms to one side:2r^6 + 5r^3 + 2 = 0Hmm, this is a quadratic in terms of r^3. Let me set y = r^3.So, equation becomes:2y^2 + 5y + 2 = 0Solving for y:Using quadratic formula: y = [-5 ± sqrt(25 - 16)] / 4 = [-5 ± sqrt(9)] / 4 = [-5 ± 3] / 4So, y = (-5 + 3)/4 = (-2)/4 = -1/2 Or y = (-5 - 3)/4 = (-8)/4 = -2So, y = -1/2 or y = -2Since y = r^3, we have:Case 1: r^3 = -1/2 So, r = (-1/2)^(1/3) = - (1/2)^(1/3) ≈ -0.7937Case 2: r^3 = -2 So, r = (-2)^(1/3) = -2^(1/3) ≈ -1.26Hmm, okay. So, let's find a_1 for each case.Case 1: r^3 = -1/2From equation (2): a_1 * r^3 (1 + r^3) = 2 Plug in r^3 = -1/2:a_1 * (-1/2) * (1 - 1/2) = 2 Simplify: a_1 * (-1/2) * (1/2) = 2 = a_1 * (-1/4) = 2 So, a_1 = 2 / (-1/4) = -8Case 2: r^3 = -2From equation (2): a_1 * (-2) * (1 - 2) = 2 Simplify: a_1 * (-2) * (-1) = 2 = a_1 * 2 = 2 So, a_1 = 1Now, we need to find a_1 + a_10 for each case.First, let's find a_10 in each case.Case 1: a_1 = -8, r^3 = -1/2 So, r = (-1/2)^(1/3). Let's compute a_10:a_10 = a_1 * r^9 But r^9 = (r^3)^3 = (-1/2)^3 = -1/8 So, a_10 = -8 * (-1/8) = 1 Therefore, a_1 + a_10 = -8 + 1 = -7Case 2: a_1 = 1, r^3 = -2 So, r = (-2)^(1/3). Let's compute a_10:a_10 = a_1 * r^9 But r^9 = (r^3)^3 = (-2)^3 = -8 So, a_10 = 1 * (-8) = -8 Therefore, a_1 + a_10 = 1 + (-8) = -7So, in both cases, a_1 + a_10 is -7.Alright, so to recap:For the arithmetic progression, a_1 * a_10 = -728 For the geometric progression, a_1 + a_10 = -7I think that's it. Let me just double-check my calculations to make sure I didn't make any mistakes.In the arithmetic progression part, I solved for d and a_1 correctly, and both cases gave the same product, which makes sense because the terms are just swapped with opposite signs. So, their product remains the same.In the geometric progression part, I had to solve a quadratic in terms of r^3, which gave me two possible values for r^3, leading to two cases for a_1. Both cases, when calculating a_1 + a_10, gave me the same result, which is consistent because the terms are inverses in a way, leading to the same sum.Yeah, I think I did this correctly.**Final Answer**For the arithmetic progression, (a_{1}a_{10} = boxed{-728}); for the geometric progression, (a_{1} + a_{10} = boxed{-7}).
question:Calculate the hypotenuse of a right triangle if the sum of the legs is ( p ), and the sum of the two segments connecting the right angle vertex to the trisection points of the hypotenuse is ( q ).
answer:Okay, so I have this problem about a right triangle where the sum of the legs is p, and the sum of two segments connecting the right angle vertex to the trisection points of the hypotenuse is q. I need to find the hypotenuse. Hmm, let me try to visualize this.First, let's draw a right triangle ABC with the right angle at C. The hypotenuse is AB. The trisection points on AB would be two points, let's call them D and E, such that AD = DE = EB. So, D is one-third of the way from A to B, and E is two-thirds of the way.Now, the problem says that the sum of the two segments connecting the right angle vertex (which is C) to these trisection points D and E is q. So, we're looking at the lengths of CD and CE, and their sum is q.Given that, and knowing that the sum of the legs AC and BC is p, I need to find the hypotenuse AB.Let me denote the legs as a and b, so AC = a and BC = b. Then, the hypotenuse AB = c, and by the Pythagorean theorem, c = sqrt(a² + b²). But since I don't know a and b individually, just their sum, which is p, I need another equation involving a and b to solve for c.The other condition is about the sum of the segments CD and CE being q. So, I need expressions for CD and CE in terms of a and b.To find CD and CE, I can use coordinate geometry. Let's place the triangle in a coordinate system with point C at the origin (0,0), point A at (a,0), and point B at (0,b). Then, the hypotenuse AB goes from (a,0) to (0,b). The trisection points D and E can be found using the section formula.Point D divides AB in the ratio 1:2, so its coordinates are ((2a + 0)/3, (0 + 2b)/3) = (2a/3, 2b/3). Similarly, point E divides AB in the ratio 2:1, so its coordinates are ((a + 0)/3, (0 + b)/3) = (a/3, b/3).Wait, no, that's not quite right. The section formula for a point dividing a line segment in the ratio m:n is ((mx2 + nx1)/(m + n), (my2 + ny1)/(m + n)). So, for point D, which is closer to A, the ratio is 1:2, meaning from A to D is 1 part and from D to B is 2 parts. So, coordinates of D would be ((1*0 + 2*a)/3, (1*b + 2*0)/3) = (2a/3, b/3). Similarly, point E, which is closer to B, would divide AB in the ratio 2:1, so coordinates are ((2*0 + 1*a)/3, (2*b + 1*0)/3) = (a/3, 2b/3).Wait, that makes more sense. So, D is (2a/3, b/3) and E is (a/3, 2b/3). Now, I need to find the lengths of CD and CE.Since point C is at (0,0), the distance from C to D is sqrt((2a/3 - 0)² + (b/3 - 0)²) = sqrt((4a²/9) + (b²/9)) = (1/3)sqrt(4a² + b²). Similarly, the distance from C to E is sqrt((a/3 - 0)² + (2b/3 - 0)²) = sqrt((a²/9) + (4b²/9)) = (1/3)sqrt(a² + 4b²).So, CD = (1/3)sqrt(4a² + b²) and CE = (1/3)sqrt(a² + 4b²). The sum of these is q, so:(1/3)sqrt(4a² + b²) + (1/3)sqrt(a² + 4b²) = qMultiplying both sides by 3:sqrt(4a² + b²) + sqrt(a² + 4b²) = 3qNow, I have two equations:1. a + b = p2. sqrt(4a² + b²) + sqrt(a² + 4b²) = 3qI need to solve these two equations for a and b, and then find c = sqrt(a² + b²).This seems a bit complicated. Maybe I can square both sides of the second equation to eliminate the square roots. Let's try that.Let me denote S = sqrt(4a² + b²) + sqrt(a² + 4b²) = 3qThen, S² = (sqrt(4a² + b²) + sqrt(a² + 4b²))² = 9q²Expanding the left side:(4a² + b²) + (a² + 4b²) + 2*sqrt{(4a² + b²)(a² + 4b²)} = 9q²Simplify:4a² + b² + a² + 4b² + 2*sqrt{(4a² + b²)(a² + 4b²)} = 9q²Combine like terms:5a² + 5b² + 2*sqrt{(4a² + b²)(a² + 4b²)} = 9q²Hmm, that's still complicated. Maybe I can isolate the square root term.Let me subtract 5a² + 5b² from both sides:2*sqrt{(4a² + b²)(a² + 4b²)} = 9q² - 5a² - 5b²Divide both sides by 2:sqrt{(4a² + b²)(a² + 4b²)} = (9q² - 5a² - 5b²)/2Now, square both sides again to eliminate the square root:(4a² + b²)(a² + 4b²) = [(9q² - 5a² - 5b²)/2]^2Let me compute the left side first:(4a² + b²)(a² + 4b²) = 4a²*a² + 4a²*4b² + b²*a² + b²*4b²= 4a⁴ + 16a²b² + a²b² + 4b⁴= 4a⁴ + 17a²b² + 4b⁴Now, the right side:[(9q² - 5a² - 5b²)/2]^2 = (9q² - 5a² - 5b²)² / 4Expanding the numerator:(9q²)^2 + (-5a²)^2 + (-5b²)^2 + 2*(9q²*(-5a²) + 9q²*(-5b²) + (-5a²)*(-5b²))= 81q⁴ + 25a⁴ + 25b⁴ + 2*(-45q²a² - 45q²b² + 25a²b²)= 81q⁴ + 25a⁴ + 25b⁴ - 90q²a² - 90q²b² + 50a²b²So, putting it all together:4a⁴ + 17a²b² + 4b⁴ = [81q⁴ + 25a⁴ + 25b⁴ - 90q²a² - 90q²b² + 50a²b²] / 4Multiply both sides by 4 to eliminate the denominator:16a⁴ + 68a²b² + 16b⁴ = 81q⁴ + 25a⁴ + 25b⁴ - 90q²a² - 90q²b² + 50a²b²Bring all terms to the left side:16a⁴ + 68a²b² + 16b⁴ - 81q⁴ - 25a⁴ - 25b⁴ + 90q²a² + 90q²b² - 50a²b² = 0Combine like terms:(16a⁴ - 25a⁴) + (68a²b² - 50a²b²) + (16b⁴ - 25b⁴) + 90q²a² + 90q²b² - 81q⁴ = 0= (-9a⁴) + (18a²b²) + (-9b⁴) + 90q²a² + 90q²b² - 81q⁴ = 0Factor out common terms:-9(a⁴ - 2a²b² + b⁴) + 90q²(a² + b²) - 81q⁴ = 0Notice that a⁴ - 2a²b² + b⁴ = (a² - b²)², so:-9(a² - b²)² + 90q²(a² + b²) - 81q⁴ = 0Divide the entire equation by -9 to simplify:(a² - b²)² - 10q²(a² + b²) + 9q⁴ = 0Now, let's recall that a + b = p. Let me denote s = a + b = p, and t = ab. Then, a² + b² = s² - 2t, and (a² - b²)² = (a² + b²)² - 4a²b² = (s² - 2t)² - 4t² = s⁴ - 4s²t + 4t² - 4t² = s⁴ - 4s²t.So, substituting into the equation:(s⁴ - 4s²t) - 10q²(s² - 2t) + 9q⁴ = 0Expand:s⁴ - 4s²t - 10q²s² + 20q²t + 9q⁴ = 0Now, let's collect like terms:s⁴ - 10q²s² + 9q⁴ - 4s²t + 20q²t = 0Factor terms with t:s⁴ - 10q²s² + 9q⁴ + t(-4s² + 20q²) = 0We can solve for t:t(-4s² + 20q²) = -s⁴ + 10q²s² - 9q⁴So,t = (-s⁴ + 10q²s² - 9q⁴) / (-4s² + 20q²)Simplify numerator and denominator:Numerator: -s⁴ + 10q²s² - 9q⁴ = -(s⁴ - 10q²s² + 9q⁴) = -(s² - q²)(s² - 9q²)Denominator: -4s² + 20q² = -4(s² - 5q²)So,t = [-(s² - q²)(s² - 9q²)] / [-4(s² - 5q²)] = [(s² - q²)(s² - 9q²)] / [4(s² - 5q²)]Since s = p, we have:t = ab = [(p² - q²)(p² - 9q²)] / [4(p² - 5q²)]Now, recall that a² + b² = c² = s² - 2t = p² - 2tSubstitute t:c² = p² - 2 * [(p² - q²)(p² - 9q²)] / [4(p² - 5q²)] = p² - [(p² - q²)(p² - 9q²)] / [2(p² - 5q²)]Let me compute this:c² = [2p²(p² - 5q²) - (p² - q²)(p² - 9q²)] / [2(p² - 5q²)]Expand the numerator:2p²(p² - 5q²) = 2p⁴ - 10p²q²(p² - q²)(p² - 9q²) = p⁴ - 9p²q² - p²q² + 9q⁴ = p⁴ - 10p²q² + 9q⁴So,Numerator = (2p⁴ - 10p²q²) - (p⁴ - 10p²q² + 9q⁴) = 2p⁴ - 10p²q² - p⁴ + 10p²q² - 9q⁴ = p⁴ - 9q⁴Therefore,c² = (p⁴ - 9q⁴) / [2(p² - 5q²)]So, c = sqrt[(p⁴ - 9q⁴)/(2(p² - 5q²))]I should check if this makes sense. For the square root to be real, the numerator and denominator must have the same sign. Since p and q are lengths, they are positive. Let's see:Denominator: 2(p² - 5q²). So, p² > 5q² to make the denominator positive. Numerator: p⁴ - 9q⁴. If p² > 5q², then p⁴ > 25q⁴, so p⁴ - 9q⁴ > 16q⁴ > 0. So, both numerator and denominator are positive, which is good.Also, from the earlier steps, we had t = ab = [(p² - q²)(p² - 9q²)] / [4(p² - 5q²)]. For t to be positive, since a and b are positive lengths, the numerator and denominator must have the same sign.Given p² > 5q², denominator is positive. So, numerator must also be positive:(p² - q²)(p² - 9q²) > 0Since p² > 5q², p² - q² > 4q² > 0, and p² - 9q². If p² > 9q², then both factors are positive, but if 5q² < p² < 9q², then p² - 9q² < 0, making the numerator negative, which would make t negative, which is impossible since t = ab > 0.Therefore, to have t positive, we must have p² - 9q² > 0, so p² > 9q². But wait, earlier we had p² > 5q². So, combining these, we must have p² > 9q² for t to be positive. But wait, let's see:Wait, if p² > 9q², then p² - 5q² > 4q² > 0, and p² - q² > 8q² > 0, p² - 9q² > 0, so numerator is positive, denominator is positive, t is positive.But if 5q² < p² < 9q², then p² - 9q² < 0, so numerator is negative, denominator is positive, so t negative, which is impossible. So, to have t positive, we must have p² > 9q².But wait, in the problem statement, it's just given that the sum of the legs is p and the sum of the segments is q. So, perhaps there's a restriction on p and q such that p² > 9q².Alternatively, maybe I made a miscalculation earlier. Let me check.Wait, when I had t = ab = [(p² - q²)(p² - 9q²)] / [4(p² - 5q²)], for t to be positive, since denominator is positive when p² > 5q², the numerator must also be positive. So, (p² - q²)(p² - 9q²) > 0.This product is positive if both factors are positive or both are negative.Case 1: Both positive.p² - q² > 0 and p² - 9q² > 0 => p² > q² and p² > 9q² => p² > 9q².Case 2: Both negative.p² - q² < 0 and p² - 9q² < 0 => p² < q² and p² < 9q². But since p is the sum of the legs, which are positive, p > a and p > b, so p > sqrt(a² + b²) = c. But c is the hypotenuse, so p > c. But c = sqrt(a² + b²) < a + b = p, so p > c, which is consistent. However, if p² < q², but q is the sum of two segments, which are each less than c, so q < 2c. Since p > c, q < 2p. But p² < q² would imply p < q, but p > c and q < 2c, so p < q would imply c < p < q < 2c, which is possible if c < p < q < 2c. But let's see:If p² < q², then p < q. But from the problem, p is the sum of the legs, and q is the sum of two segments. Each segment is less than c, so q < 2c. But p > c, so p could be between c and 2c, and q could be between c and 2c as well. So, it's possible that p < q, but then p² < q². However, in this case, t would be positive only if both factors are negative, which would require p² < q² and p² < 9q², which is automatically true if p² < q². So, t could be positive in both cases where p² > 9q² or p² < q².But wait, if p² < q², then p < q, but p is the sum of the legs, and q is the sum of two segments. Each segment is less than c, so q < 2c. But p > c, so p could be less than q if q > c. But p is the sum of the legs, which is greater than c, so p > c. If q is the sum of two segments, each less than c, so q < 2c. So, p is between c and 2c, and q is between c and 2c as well. So, it's possible that p < q or p > q depending on the specific triangle.But in our earlier step, we found that t = ab must be positive, so either p² > 9q² or p² < q². However, p is the sum of the legs, which is greater than c, and q is the sum of two segments, each less than c, so q < 2c. Since p > c, p could be greater than q or less than q. But if p² < q², then p < q, but p > c, so q must be greater than c as well. However, q is the sum of two segments, each less than c, so q < 2c. So, p could be between c and 2c, and q could be between c and 2c, so p could be greater or less than q.But in our equation, t must be positive, so either p² > 9q² or p² < q². However, if p² < q², then p < q, but p is the sum of the legs, which is greater than c, and q is less than 2c. So, p could be less than q if q > p, but p is already greater than c. So, it's possible if q > p, but then p < q, which would require p² < q². However, in that case, t would be positive because both factors in the numerator would be negative, making the numerator positive, and denominator positive as well since p² - 5q² would be negative if p² < q², but wait, denominator is 4(p² - 5q²). If p² < q², then p² - 5q² < 0, so denominator would be negative. Numerator is (p² - q²)(p² - 9q²). If p² < q², then p² - q² < 0, and p² - 9q² < 0, so numerator is positive. So, t = positive / negative = negative, which is impossible because t = ab > 0. Therefore, the case p² < q² leads to t negative, which is impossible. Therefore, the only valid case is p² > 9q², making both numerator and denominator positive, so t positive.Therefore, the condition is p² > 9q².So, the hypotenuse c is sqrt[(p⁴ - 9q⁴)/(2(p² - 5q²))].Let me check the dimensions. p and q are lengths, so p⁴ and q⁴ are lengths to the fourth power, and p² and q² are lengths squared. So, the expression inside the square root is (length⁴)/(length²) = length², so c has dimensions of length, which is correct.Also, if q approaches zero, meaning the trisection points are very close to the endpoints, then the sum of the segments CD + CE approaches the lengths of the legs, but since q is the sum, it's more complicated. Alternatively, if q is very small, then c² ≈ p⁴ / (2p²) = p²/2, so c ≈ p/sqrt(2), which makes sense if the triangle is isosceles with legs p/2 each, but wait, if the triangle is isosceles, then a = b = p/2, so c = sqrt(2*(p/2)²) = p/sqrt(2). So, that checks out.Alternatively, if q is such that p² = 9q², then c² would be (p⁴ - 9q⁴)/(2(p² - 5q²)) = (81q⁴ - 9q⁴)/(2(9q² - 5q²)) = (72q⁴)/(8q²) = 9q², so c = 3q. But if p² = 9q², then p = 3q, and from earlier, t = ab = [(9q² - q²)(9q² - 9q²)] / [4(9q² - 5q²)] = [(8q²)(0)] / [4(4q²)] = 0, which implies either a or b is zero, which is not possible. So, p cannot equal 3q, only p > 3q.Therefore, the final expression for c is sqrt[(p⁴ - 9q⁴)/(2(p² - 5q²))].
question:A restaurant offers diet soda and regular soda. In one day they sold some sodas. If 28 of the sodas they sold were diet, and the ratio of regular sodas sold to diet sodas sold is 9:7, how many sodas did they sell in total?
answer:First, I recognize that the problem involves a ratio of regular sodas to diet sodas, which is given as 9:7.I know that 28 diet sodas were sold. To find the number of regular sodas sold, I can set up a proportion based on the given ratio:9/7 = R/28By cross-multiplying, I get:9 * 28 = 7 * R252 = 7RSolving for R:R = 252 / 7R = 36So, 36 regular sodas were sold.To find the total number of sodas sold, I add the number of regular sodas to the number of diet sodas:Total sodas = 36 + 28 = 64Therefore, the restaurant sold a total of 64 sodas.
question:There are 20 players on a rugby team with an average weight of 180 pounds. If three new players join the team with weights of 210 pounds, 220 pounds, and 230 pounds respectively, what will be the new average weight of the team?
answer:First, I need to determine the total weight of the original 20 players on the rugby team. Since the average weight is 180 pounds, I can calculate the total weight by multiplying the number of players by the average weight.Next, I'll add the weights of the three new players to the total weight of the original team. This will give me the new total weight of the team after the new players have joined.After finding the new total weight, I'll calculate the new number of players on the team by adding the original number of players to the number of new players.Finally, I'll compute the new average weight by dividing the new total weight by the new number of players. This will provide the updated average weight of the entire team.