The possible price of the magazine can be either $ 9 , $ 6 , or $3
First we need to understand the different between a cost and a price. A cost is the amount of money needed to Produce the magazine, while a price is the amount of money that the sellers get when he hand it over to customer
since its said the cost is in multiple of $ 3 , the possible price of two magazine would be :
$ 9 + $3 = $ 12
$6 + $6 = $ 12
$3 + $ 9 = $ 12
