The ratio of the number of wafers to the number of biscuits in a stall is 3 : 1. A wafer costs $1.30 and a biscuit costs $0.50. If all the wafers and biscuits are sold, a sum of $132 will be collected. How many wafers are there altogether?
| |
Wafers |
Biscuits |
Total |
| Number |
3 u |
1 u |
|
| Value |
$1.30 |
$0.50 |
|
| Total value |
3.9 u |
0.5 u |
$132 |
Amount collected if all the wafers are sold
= 3 u x 1.3
= 3.9 u
Amount collected if all the biscuits are sold
= 1 u x 0.5 u
= 0.5 u
Amount collected if all the wafers and biscuits are sold
= 3.9 u + 0.5 u
= 4.4 u
4.4 u = 132
1 u = 132 ÷ 4.4 = 30
Total number of wafers
= 3 u
= 3 x 30
= 90
Answer(s): 90
