180 pupils went for a physical fitness test and 76 of them achieved Bronze certificates.
35 of the boys and
15 of the girls achieved Bronze certificates. How many boys did not achieve Bronze certificates?
| Girls |
Boys |
| 5 u |
5 p |
Achieved
Bronze |
Did not achieve
Bronze |
Achieved
Bronze |
Did not achieve
Bronze |
| 3 u |
2 u |
1 p |
4 p |
Number of pupils who did not achieve Bronze certificates
= 180 - 76
= 104
3 u + 1 p = 76
1 p = 76 - 3 u --- (1)
2 u + 4 p = 104
4 p = 104 - 2 u --- (2)
Make p the same.
(1)
x44 p = 304 - 12 u --- (3)
(2) = (3)
104 - 2 u = 304 - 12 u
12 u - 2 u = 304 - 104
10 u = 200
1 u = 200 ÷ 10 = 20
Number of girls who did not achieve Bronze certificates
= 2 u
= 2 x 20
= 40
Number of boys who did not achieve Bronze certificates
= 104 - 40
= 64
Answer(s): 64
