During a donation drive, $2200 was collected by 60 students. Each girl donated $50 and each boy donated $10. 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 10 = $10 |
$2960 |
40
|
40 x 50 = $2000 |
20
|
20 x 10 = $200 |
$2200
|
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 - 2200
= $800
Small difference in the amount made between one girl and one boy
= 50 - 10
= $40
Number of boys
= 800 ÷ 40
= 20
Number of girls
= 60 - 20
= 40
Answer(s): 40