In one Mathematics class of 100 students, 0.25 of the boys and
23 of the girls passed the mock test. A total of 30 students passed the mock test. How many boys failed the Mathematics mock test?
|
Boys |
Girls |
Total |
Passed the test |
1 u |
2 p |
30 |
Failed the test |
3 u |
1 p |
70 |
Total |
4 u |
3 p |
100 |
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 = 30 --- (1)
3 u + 1 p = 100 - 30
3 u + 1 p = 70 --- (2)
Make u the same.
(1)
x33 u + 6 p = 90 --- (3)
(3) - (2)
6 p - 1 p = 90 - 70
5 p = 20
1 p = 20 ÷ 5 = 4
From (2)
Number of boys who failed
= 70 - 1 p
= 70 - 4
= 66
Answer(s): 66