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Dr. Li Zhengdao gave a math problem to the junior students of China University of Science and Technology. How to solve it?
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We add 4 peaches to the original X peaches, and consider x+4. At this time, we don't need to throw them into the sea.

But let each monkey get one more, that is, always get the rest 1/5, then X must make

(x+4) * (4/5) 5 is an integer,

In other words, the minimum value of (x+4) should be equal to 5 5 = 3125, min. x = 3 12 1。

The answer should be 3 12 1 peach.

First of all, 4 and 5 are prime numbers, so 4/5 of a number can be divisible by 5, which is equivalent to 1/5 of a number being divisible by 5. Secondly, throwing away 1 at first is the same as adding four (after adding four, one more person is responsible for dividing things, which is equivalent to throwing away);

The total is (x+4) = 5 * 5 * 5 = 3125, so =3 12 1.

3 12 1 is the correct answer. Verification:

3 12 1

(3121-1) * 4/5 = 3120-624 = 2496 The first monkey takes 624.

(2496-1) * 4/5 = 2495-499 =1996 The second monkey took 499.

(1996-1) * 4/5 =1995-399 =1596 The third monkey takes 399.

(1596-1) * 4/5 =1595-3 19 =1276 The fourth monkey takes 319.

(1276-1) * 4/5 =1275-255 =1020 The fifth monkey takes 255.