Question

The cost of a book is $x. Write down an expression in terms of "x" for the number of these books which are bought for $40.

Answer 1

40/x is the expression

Answer 2

In x dollars,
number of book that can be bought = 1

So, In 1 dollar,
number of books that can be bought = 1/x

Hence in 40 dollars,
number of books that can be bought = 40/x