The ratio of the number of wafers to the number of biscuits in a shop is 4 : 1. A wafer costs $1.70 and a biscuit costs $0.40. If all the wafers and biscuits are sold, a sum of $216 will be collected. How many wafers are there altogether?
| |
Wafers |
Biscuits |
Total |
| Number |
4 u |
1 u |
|
| Value |
$1.70 |
$0.40 |
|
| Total value |
6.8 u |
0.4 u |
$216 |
Amount collected if all the wafers are sold
= 4 u x 1.7
= 6.8 u
Amount collected if all the biscuits are sold
= 1 u x 0.4 u
= 0.4 u
Amount collected if all the wafers and biscuits are sold
= 6.8 u + 0.4 u
= 7.2 u
7.2 u = 216
1 u = 216 ÷ 7.2 = 30
Total number of wafers
= 4 u
= 4 x 30
= 120
Answer(s): 120
