The ratio of the number of shortbreads to the number of muffins in a supermarket is 3 : 1. A shortbread costs $1.60 and a muffin costs $0.70. If all the shortbreads and muffins are sold, a sum of $55 will be collected. How many shortbreads are there altogether?
| |
Shortbreads |
Muffins |
Total |
| Number |
3 u |
1 u |
|
| Value |
$1.60 |
$0.70 |
|
| Total value |
4.8 u |
0.7 u |
$55 |
Amount collected if all the shortbreads are sold
= 3 u x 1.6
= 4.8 u
Amount collected if all the muffins are sold
= 1 u x 0.7 u
= 0.7 u
Amount collected if all the shortbreads and muffins are sold
= 4.8 u + 0.7 u
= 5.5 u
5.5 u = 55
1 u = 55 ÷ 5.5 = 10
Total number of shortbreads
= 3 u
= 3 x 10
= 30
Answer(s): 30
