The ratio of the number of shortbreads to the number of biscuits in a kiosk is 3 : 1. A shortbread costs $1.60 and a biscuit costs $0.30. If all the shortbreads and biscuits are sold, a sum of $153 will be collected. How many shortbreads are there altogether?
| |
Shortbreads |
Biscuits |
Total |
| Number |
3 u |
1 u |
|
| Value |
$1.60 |
$0.30 |
|
| Total value |
4.8 u |
0.3 u |
$153 |
Amount collected if all the shortbreads are sold
= 3 u x 1.6
= 4.8 u
Amount collected if all the biscuits are sold
= 1 u x 0.3 u
= 0.3 u
Amount collected if all the shortbreads and biscuits are sold
= 4.8 u + 0.3 u
= 5.1 u
5.1 u = 153
1 u = 153 ÷ 5.1 = 30
Total number of shortbreads
= 3 u
= 3 x 30
= 90
Answer(s): 90
