In one History class of 115 students, 0.25 of the girls and
23 of the boys passed the mock test. A total of 35 students passed the mock test. How many girls failed the History mock test?
| |
Girls |
Boys |
Total |
| Passed the test |
1 u |
2 p |
35 |
| Failed the test |
3 u |
1 p |
80 |
| Total |
4 u |
3 p |
115 |
0.25 of the girls =
14 of the girls
Total number of girls = 4 u
Total number of boys = 3 p
1 u + 2 p = 35 --- (1)
3 u + 1 p = 115 - 35
3 u + 1 p = 80 --- (2)
Make u the same.
(1)
x33 u + 6 p = 105 --- (3)
(3) - (2)
6 p - 1 p = 105 - 80
5 p = 25
1 p = 25 ÷ 5 = 5
From (2)
Number of girls who failed
= 80 - 1 p
= 80 - 5
= 75
Answer(s): 75
