In one Chinese class of 115 students, 0.25 of the boys and
45 of the girls passed the exam. A total of 48 students passed the exam. How many boys failed the Chinese exam?
| |
Boys |
Girls |
Total |
| Passed the test |
1 u |
4 p |
48 |
| Failed the test |
3 u |
1 p |
67 |
| Total |
4 u |
5 p |
115 |
0.25 of the boys =
14 of the boys
Total number of boys = 4 u
Total number of girls = 5 p
1 u + 4 p = 48 --- (1)
3 u + 1 p = 115 - 48
3 u + 1 p = 67 --- (2)
Make u the same.
(1)
x33 u + 12 p = 144 --- (3)
(3) - (2)
12 p - 1 p = 144 - 67
11 p = 77
1 p = 77 ÷ 11 = 7
From (2)
Number of boys who failed
= 67 - 1 p
= 67 - 7
= 60
Answer(s): 60
