Marion wanted to buy some biscuits and shortbreads. The cost of a biscuit was
15 the cost of a shortbread. A set of 7 biscuits and 2 shortbreads cost $13.60. What was the total amount Marion had to pay for 4 biscuits and 8 shortbreads?
| |
Biscuits |
Shortbreads |
Total |
| Number |
7 |
2 |
|
| Value |
1 u |
5 u |
|
| Total value |
7 u |
10 u |
17 u |
Total cost of biscuits and shortbreads
= 7 u + 10 u
= 17 u
17 u = 13.6
1 u = 13.60 ÷ 17 = 0.8
Cost of 4 biscuits and 8 shortbreads
= 4 x 1 u + 8 x 5 u
= 4 u + 40 u
= 44 u
= 44 x 0.8
= $35.20
Answer(s): $35.20
