In one Science class of 112 students, 0.25 of the boys and
34 of the girls passed the exam. A total of 50 students passed the exam. How many boys failed the Science exam?
| |
Boys |
Girls |
Total |
| Passed the test |
1 u |
3 p |
50 |
| Failed the test |
3 u |
1 p |
62 |
| Total |
4 u |
4 p |
112 |
0.25 of the boys =
14 of the boys
Total number of boys = 4 u
Total number of girls = 4 p
1 u + 3 p = 50 --- (1)
3 u + 1 p = 112 - 50
3 u + 1 p = 62 --- (2)
Make u the same.
(1)
x33 u + 9 p = 150 --- (3)
(3) - (2)
9 p - 1 p = 150 - 62
8 p = 88
1 p = 88 ÷ 8 = 11
From (2)
Number of boys who failed
= 62 - 1 p
= 62 - 11
= 51
Answer(s): 51
