In one Mathematics class of 112 students, 0.25 of the boys and
23 of the girls passed the mock test. A total of 33 students passed the mock test. How many boys failed the Mathematics mock test?
| |
Boys |
Girls |
Total |
| Passed the test |
1 u |
2 p |
33 |
| Failed the test |
3 u |
1 p |
79 |
| Total |
4 u |
3 p |
112 |
0.25 of the boys =
14 of the boys
Total number of boys = 4 u
Total number of girls = 3 p
1 u + 2 p = 33 --- (1)
3 u + 1 p = 112 - 33
3 u + 1 p = 79 --- (2)
Make u the same.
(1)
x33 u + 6 p = 99 --- (3)
(3) - (2)
6 p - 1 p = 99 - 79
5 p = 20
1 p = 20 ÷ 5 = 4
From (2)
Number of boys who failed
= 79 - 1 p
= 79 - 4
= 75
Answer(s): 75
