Question

A bookstore had 80 copies of a magazine. Yesterday, it sold 2/5 of them. Today, it sold 1/4 of what remained. How many copies does the bookstore have left?

Answer 1

 (80 x 3/5) x 3/4
= 48 x 3/4 
= 36 copies will be left
 

Answer 2

Sold: (2/5)(80) = (2)16 = 32
Remaining: 80-32= 48
.
Today:
Sold: (3/4)(48) = (3)12 = 12
Left over: 48-12 = 36 magazines