Respuesta :
you add 10 to the 32 to get 42 and then divide by the original cost of the books ($7) to get 6. so, John bought 6 books.
John bought 6 books
$10 credit + $32 cost after his credit was applied = $42 total cost
$42 divided by $7 (for the cost of one book) = 6 books
$10 credit + $32 cost after his credit was applied = $42 total cost
$42 divided by $7 (for the cost of one book) = 6 books