114 students went for a singing competition and 36 of them achieved Bronze certificates.
25 of the girls and
14 of the boys achieved Bronze certificates. How many girls did not achieve Bronze certificates?
| Boys |
Girls |
| 5 u |
4 p |
Achieved
Bronze |
Did not achieve
Bronze |
Achieved
Bronze |
Did not achieve
Bronze |
| 2 u |
3 u |
1 p |
3 p |
Number of students who did not achieve Bronze certificates
= 114 - 36
= 78
2 u + 1 p = 36
1 p = 36 - 2 u --- (1)
3 u + 3 p = 78
3 p = 78 - 3 u --- (2)
Make p the same.
(1)
x33 p = 108 - 6 u --- (3)
(2) = (3)
78 - 3 u = 108 - 6 u
6 u - 3 u = 108 - 78
3 u = 30
1 u = 30 ÷ 3 = 10
Number of boys who did not achieve Bronze certificates
= 3 u
= 3 x 10
= 30
Number of girls who did not achieve Bronze certificates
= 78 - 30
= 48
Answer(s): 48
