Question

There were some toys in a store. At first, all the toys were placed on 36 shelves with equal number of toys on each shelf. 8 shelves were removed and the toys on these shelves were placed on the remaining shelves. As a result, the number of toys on each remaining shelf increased by 4. How many toys were there in the store?

Answer 1

The number of toys must be a multiple of 36 , let the number of toys be 36x
where x is the number of toys on each shelf

after 8 shelves were removed,
number of toys on each shelf
= 36x/28
= x+4

36x/28 = x+4
36x = 28x + 112
x = 14

number of toys in the store = 36x = 504

check:
toys on each shelf at the beginning = 504/36 = 14
toys on each shelf after 8 were removed = 504/28 = 18
which is 4 more per shelf as originally.