Question

My little brother spent $53 on comic books and magazines. He bought 17 items. If comic books cost $4 and magazines cost $3, how many of each item did my brother buy?

Answer 1

Answer:

comic books = 2

magazines = 15

Step-by-step explanation:

Let c = number of comic books bought

Let m = number of magazines bought

He bought 17 items, so

c + m = 17

Comic books cost $4 each and magazines cost $3 each.

He spent $53 on comic books and magazines, so

4c + 3m = 53

Rearrange c + m = 17 to make m the subject:

m = 17 - c

Substitute  m = 17 - c  into  4c + 3m = 53  and solve for c:

4c + 3(17 - c) = 53

⇒ 4c + 51 - 3c = 53

⇒ c = 2

Substitute c = 2  into m = 17 - c to and solve for m:

m = 17 - 2 = 15