During a donation drive, $2280 was collected by 60 students. Each girl donated $50 and each boy donated $20. How many girls were there?
Number of girls |
Amount collected by girls |
Number of boys |
Amount collected by boys |
Total amount collected |
60
|
60 x 50 = $3000 |
0 |
0
|
$3000 |
59
|
59 x 50 = $2950 |
1 |
1 x 20 = $20 |
$2970 |
36
|
36 x 50 = $1800 |
24
|
24 x 20 = $480 |
$2280
|
Total amount collected if all the donations were made by girls
= 60 x 50
= $3000
Big difference in the total amounts made between the girls and the boys
= 3000 - 2280
= $720
Small difference in the amount made between one girl and one boy
= 50 - 20
= $30
Number of boys
= 720 ÷ 30
= 24
Number of girls
= 60 - 24
= 36
Answer(s): 36