The ratio of the number of cupcakes to the number of puffs in a stall is 3 : 1. A cupcake costs $1.50 and a puff costs $0.90. If all the cupcakes and puffs are sold, a sum of $108 will be collected. How many cupcakes are there altogether?
| |
Cupcakes |
Puffs |
Total |
| Number |
3 u |
1 u |
|
| Value |
$1.50 |
$0.90 |
|
| Total value |
4.5 u |
0.9 u |
$108 |
Amount collected if all the cupcakes are sold
= 3 u x 1.5
= 4.5 u
Amount collected if all the puffs are sold
= 1 u x 0.9 u
= 0.9 u
Amount collected if all the cupcakes and puffs are sold
= 4.5 u + 0.9 u
= 5.4 u
5.4 u = 108
1 u = 108 ÷ 5.4 = 20
Total number of cupcakes
= 3 u
= 3 x 20
= 60
Answer(s): 60
