Question

Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends. How much can he spend on each card if he buys the same card for each friend?

Answer 1

Model the equation
2c+8=15
Solve for c to find the cost he can spend
2c=7
c=3.5
He can spend $3.50 on each card.

Answer 2

so assuming that he buys only one $8 book
tee book cost 8 so he has 15-8 to spend on the birthday cards
15-8=7
he has 7 dollars to spend on 2 cards
how much for each
he needs to buy 2 cards with 7 dollars so to find cost per 1 card divide 7 by 2 since they are same value
7/2=3 and 1/2=3.5
he can spend $3.50 per card