During a donation drive, $1260 was collected by 50 students. Each boy donated $40 and each girl donated $20. How many boys were there?
Number of
boys |
Amount collected
by boys |
Number of
girls |
Amount collected
by girls |
Total amount
collected |
50
|
50 x 40 =
$2000 |
0 |
0
|
$2000 |
49
|
49 x 40 =
$1960 |
1 |
1 x 20 =
$20 |
$1980 |
13
|
13 x 40 =
$520 |
37
|
37 x 20 =
$740 |
$1260
|
Total amount collected if all the donations were made by boys
= 50 x 40
= $2000
Big difference in the total amounts made between the boys and the girls
= 2000 - 1260
= $740
Small difference in the amount made between one boy and one girl
= 40 - 20
= $20
Number of girls
= 740 ÷ 20
= 37
Number of boys
= 50 - 37
= 13
Answer(s): 13
