Joelle wanted to buy some tarts and cookies. The cost of a tart was
37 the cost of a cookie. A set of 4 tarts and 3 cookies cost $13.20. What was the total amount Joelle had to pay for 3 tarts and 4 cookies?
| |
Tarts |
Cookies |
Total |
| Number |
4 |
3 |
|
| Value |
3 u |
7 u |
|
| Total value |
12 u |
21 u |
33 u |
Total cost of tarts and cookies
= 12 u + 21 u
= 33 u
33 u = 13.2
1 u = 13.20 ÷ 33 = 0.4
Cost of 3 tarts and 4 cookies
= 3 x 3 u + 4 x 7 u
= 9 u + 28 u
= 37 u
= 37 x 0.4
= $14.80
Answer(s): $14.80
