The ratio of the number of tarts to the number of cookies in a shop is 3 : 1. A tart costs $1.40 and a cookie costs $0.50. If all the tarts and cookies are sold, a sum of $141 will be collected. How many tarts are there altogether?
| |
Tarts |
Cookies |
Total |
| Number |
3 u |
1 u |
|
| Value |
$1.40 |
$0.50 |
|
| Total value |
4.2 u |
0.5 u |
$141 |
Amount collected if all the tarts are sold
= 3 u x 1.4
= 4.2 u
Amount collected if all the cookies are sold
= 1 u x 0.5 u
= 0.5 u
Amount collected if all the tarts and cookies are sold
= 4.2 u + 0.5 u
= 4.7 u
4.7 u = 141
1 u = 141 ÷ 4.7 = 30
Total number of tarts
= 3 u
= 3 x 30
= 90
Answer(s): 90
