In one Chinese class of 111 pupils, 0.1 of the girls and
23 of the boys passed the test. A total of 57 pupils passed the test. How many girls failed the Chinese test?
|
Girls |
Boys |
Total |
Passed the test |
1 u |
2 p |
57 |
Failed the test |
9 u |
1 p |
54 |
Total |
10 u |
3 p |
111 |
0.1 of the girls =
110 of the girls
Total number of girls = 10 u
Total number of boys = 3 p
1 u + 2 p = 57 --- (1)
9 u + 1 p = 111 - 57
9 u + 1 p = 54 --- (2)
Make u the same.
(1)
x99 u + 18 p = 513 --- (3)
(3) - (2)
18 p - 1 p = 513 - 54
17 p = 459
1 p = 459 ÷ 17 = 27
From (2)
Number of girls who failed
= 54 - 1 p
= 54 - 27
= 27
Answer(s): 27