Question: How long is the banana?
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Question: How long is the banana?
Since we all had so much fun on the last physics question, I figured we ought to follow up with a more straightforward math puzzler:
A rope over the top of a fence has the same length on each side and weighs 1/3 of a pound per foot. On one end hangs a monkey holding a banana, and on the other end a weight equal to the weight of the monkey. The banana weighs 2 ounces per inch. The length of the rope in feet is the same as the age of the monkey, and the weight of the monkey in ounces is as much as the age of the monkeys mother. The combined ages of the monkey and its mother are 30 years. 1/2 the weight of the monkey plus banana is 1/4 the sum of the weights of the rope and the weight. The monkeys mother is 1/2 as old as the monkey will be when it is 3 times older as old as its mother was when she was 1/2 as old as the monkey will be when it is as old as its mother will be when she is 4 times as old as the monkey was when it was twice as old as its mother was when she was 1/3 as old as the monkey was when it was as old as its mother was when she was 3 times as old as the monkey was when it was 1/4 as old as it is now.
How long is the banana?
I'll post THE CORRECT ANSWER later tonight, unless someone proves it sooner...
A rope over the top of a fence has the same length on each side and weighs 1/3 of a pound per foot. On one end hangs a monkey holding a banana, and on the other end a weight equal to the weight of the monkey. The banana weighs 2 ounces per inch. The length of the rope in feet is the same as the age of the monkey, and the weight of the monkey in ounces is as much as the age of the monkeys mother. The combined ages of the monkey and its mother are 30 years. 1/2 the weight of the monkey plus banana is 1/4 the sum of the weights of the rope and the weight. The monkeys mother is 1/2 as old as the monkey will be when it is 3 times older as old as its mother was when she was 1/2 as old as the monkey will be when it is as old as its mother will be when she is 4 times as old as the monkey was when it was twice as old as its mother was when she was 1/3 as old as the monkey was when it was as old as its mother was when she was 3 times as old as the monkey was when it was 1/4 as old as it is now.
How long is the banana?
I'll post THE CORRECT ANSWER later tonight, unless someone proves it sooner...
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Originally Posted by psoper
... the weight of the monkey in ounces is as much as the age of the monkeys mother.
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This problem is ambiguous... what material is the rope made of? What's the friction coefficient of the rope and the fence? What'd the density of the banana and the string? What color is the banana? 
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I got that the length of the banana = 4/[16/3 * A - B] where A is the monkey's age and B is the mother's age.
And then I got that the monkey is 12 and the mother is 18.
But that gives me a banana that is 0.087in long...pretty small banana...
Can you tell me what half I did wrong (the age relation or all the other relations...) or did you go about it a different way?
And then I got that the monkey is 12 and the mother is 18.
But that gives me a banana that is 0.087in long...pretty small banana...
Can you tell me what half I did wrong (the age relation or all the other relations...) or did you go about it a different way?
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The banana doesn't exist, it weighs nothing and is hences zero inches long and not there.
rope is equal on both sides, it doesn't matter what it weighs, it cancels itself out. the weight weighs the same as the monkey. the system is already in equilibrium.
All that stuff about the monkey and it's mom is in relation to the length of the rope which we don't care about because we already know that it is the same length on each side.
rope is equal on both sides, it doesn't matter what it weighs, it cancels itself out. the weight weighs the same as the monkey. the system is already in equilibrium.
All that stuff about the monkey and it's mom is in relation to the length of the rope which we don't care about because we already know that it is the same length on each side.
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Originally Posted by psoper
On one end hangs a monkey holding a banana, and on the other end a weight equal to the weight of the monkey..
