a=(x+4)/5,b=4(x+4)/25,c= 16(x+4)/ 125,d=64(x+4)/625,e=256(x+4)/3 125
E should be an integer, and 256 is not divisible by 5, so (x+4) should be a multiple of 3 125, so (x+4)=3 125k(k is a natural number). When k = 1, x=3 12 1.
So five monkeys picked at least 3 12 1 peach.
(3 12 1- 1)/5 * 4 = 2496 (2496- 1)/5*4= 1996 ( 1996-66)
(1596-1)/5 * 4 =1276 (unit) (1276-1)/5 * 4 =1020 (unit).
So in the end, 1020 remains.
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