Xuan paid $20 for 5 wafers and 7 cakes. A cake cost five times as much as a wafer.
- Find the cost of a wafer in cents.
- How much more did she pay for a cake than a wafer?
| |
Wafers |
Cakes |
Total |
| Number |
5 |
7 |
|
| Value |
1 u |
5 u |
|
| Total value |
5 u |
35 u |
40 u |
(a)
Cost of 1 wafer = 1 u
Cost of 1 cake = 5 u
Cost of 5 wafers
= 5 x 1 u
= 5 u
Cost of 7 cakes
= 7 x 5 u
= 35 u
Total cost of 5 wafers and 7 cakes
= 5 u + 35 u
= 40 u
$1 = 100¢
$20 = 20 x 100 = 2000¢
40 u = 2000
1 u = 2000 ÷ 40 = 50
Cost of a bun
= 1 u
= 50¢
(b)
Amount that Xuan paid more for a cake than a wafer
= 5 u - 1 u
= 4 u
= 4 x 50
= 200¢
200¢ = $2
Answer(s): (a) 50¢ (b) $2
