98 pupils went for a spelling test and 46 of them achieved Bronze certificates.
35 of the boys and
13 of the girls achieved Bronze certificates. How many boys did not achieve Bronze certificates?
| Girls |
Boys |
| 5 u |
3 p |
Achieved
Bronze |
Did not achieve
Bronze |
Achieved
Bronze |
Did not achieve
Bronze |
| 3 u |
2 u |
1 p |
2 p |
Number of pupils who did not achieve Bronze certificates
= 98 - 46
= 52
3 u + 1 p = 46
1 p = 46 - 3 u --- (1)
2 u + 2 p = 52
2 p = 52 - 2 u --- (2)
Make p the same.
(1)
x22 p = 92 - 6 u --- (3)
(2) = (3)
52 - 2 u = 92 - 6 u
6 u - 2 u = 92 - 52
4 u = 40
1 u = 40 ÷ 4 = 10
Number of girls who achieved Bronze certificates
= 3 u
= 3 x 10
= 30
Number of boys who achieved Bronze certificates
= 46 - 30
= 16
Answer(s): 16
