In one Social Studies class of 92 students, 0.125 of the girls and
34 of the boys passed the exam. A total of 34 students passed the exam. How many girls failed the Social Studies exam?
| |
Girls |
Boys |
Total |
| Passed the test |
1 u |
3 p |
34 |
| Failed the test |
7 u |
1 p |
58 |
| Total |
8 u |
4 p |
92 |
0.125 of the girls =
18 of the girls
Total number of girls = 8 u
Total number of boys = 4 p
1 u + 3 p = 34 --- (1)
7 u + 1 p = 92 - 34
7 u + 1 p = 58 --- (2)
Make u the same.
(1)
x77 u + 21 p = 238 --- (3)
(3) - (2)
21 p - 1 p = 238 - 58
20 p = 180
1 p = 180 ÷ 20 = 9
From (2)
Number of girls who failed
= 58 - 1 p
= 58 - 9
= 49
Answer(s): 49
