The ratio of the number of puffs to the number of shortbreads in a shop is 2 : 1. A puff costs $1.70 and a shortbread costs $0.60. If all the puffs and shortbreads are sold, a sum of $80 will be collected. How many puffs are there altogether?
| |
Puffs |
Shortbreads |
Total |
| Number |
2 u |
1 u |
|
| Value |
$1.70 |
$0.60 |
|
| Total value |
3.4 u |
0.6 u |
$80 |
Amount collected if all the puffs are sold
= 2 u x 1.7
= 3.4 u
Amount collected if all the shortbreads are sold
= 1 u x 0.6 u
= 0.6 u
Amount collected if all the puffs and shortbreads are sold
= 3.4 u + 0.6 u
= 4 u
4 u = 80
1 u = 80 ÷ 4 = 20
Total number of puffs
= 2 u
= 2 x 20
= 40
Answer(s): 40
