Faridah baked some cookies. 3/8 of them were coconut cookies and 2/5 of the remainder were peanut cookies. The rest were chocolate cookies. What fraction of the cookies were chocolate cookies?
set total cookies as x
3/8x=coconut cookies
2/5*5/8 = 1/4x=peanut cookies
(rest) x-3/8x-1/4x = 3/8x accounts for chocolate cookies, so 3/8 is the fraction we're looking for