32 children in a class sold an average of 22 comic books for charity. There were 4 more boys than girls in the class. The average number of comic books sold by the boys was 15. Find the average number of comic books sold by the girls.
| |
Girls |
Boys |
Total |
| Number |
1 u |
1 u + 4 |
32 |
| Value |
? |
15 |
22 |
| Total value |
434 |
270 |
704 |
Total number of comic books sold
= 32 x 22
= 704
Number of girls = 1 u
Number of boys = 1 u + 4
1 u + 1 u + 4 = 32
2 u + 4 = 32
2 u = 32 - 4
2 u = 28
1 u = 28 ÷ 2 = 14
Number of boys in class
= 1 u + 4
= 14 + 4
= 18
Number of comic books sold by boys
= 18 x 15
= 270
Number of comic books sold by girls
= 704 - 270
= 434
Average number of comic books sold by girls
= 434 ÷ 14
= 31
Answer(s): 31
