PSLE The students of a test are divided equally into two groups. In the first group, there are 33 more girls than boys. In the second group, there are 11 more boys than girls. 40% of all the students are boys. How many students are girls?
|
First group |
Second group |
Total |
Comparison 1 |
50% |
50% |
100% |
Comparison 2 |
Girls (more) |
Boys (less)
|
Girls (less)
|
Boys (more) |
|
|
1 u + 33 |
1 u |
1 u + 11 |
1 u + 11 + 11 |
|
Comparison 3 |
Total boys |
Total girls |
|
|
40% |
60% |
100% |
Number of students in the first group and the second group is equal.
Percentage of students who are girls
= 100% - 40%
= 60%
Percentage of more girls than boys
= 60% - 40%
= 20%
Total number of girls
= 1 u + 33 + 1 u + 11
= 2 u + 44
Total number of boys
= 1 u + 1 u + 11 + 11
= 2 u + 22
Number of girls more than boys
= 44 - 22
= 22
20% of the students = 22
1% of the students = 22 ÷ 20 = 1.1
60% of the students
= 60 x 1.1
= 66
Number of students that are girls = 66
Answer(s): 66