In one Social Studies class of 102 students, 0.25 of the boys and
45 of the girls passed the test. A total of 64 students passed the test. How many boys failed the Social Studies test?
|
Boys |
Girls |
Total |
Passed the test |
1 u |
4 p |
64 |
Failed the test |
3 u |
1 p |
38 |
Total |
4 u |
5 p |
102 |
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 = 64 --- (1)
3 u + 1 p = 102 - 64
3 u + 1 p = 38 --- (2)
Make u the same.
(1)
x33 u + 12 p = 192 --- (3)
(3) - (2)
12 p - 1 p = 192 - 38
11 p = 154
1 p = 154 ÷ 11 = 14
From (2)
Number of boys who failed
= 38 - 1 p
= 38 - 14
= 24
Answer(s): 24