PSLE Pupils in a school are put into two groups for an excursion.
13 of the pupils are in Group A and the rest in Group B.
57 of the pupils in Group A are boys. In the school,
57 of the pupils are boys. What fraction of the pupils in Group B are girls?
Group A |
Group B |
Total |
1x7 |
2x7 |
3x7 |
|
|
7x3 |
7 u |
14 u |
21 u |
Boys |
Girls |
Boys |
Girls |
Boys |
Girls |
5 |
2 |
|
|
5x3 |
2x3 |
5 u |
2 u |
10 u |
4 u |
15 u |
6 u |
The total number of students is repeated.
Make the total number of students the same.
LCM of 3 and 7 is 21.
Number of boys in Group B
= 15 u - 5 u
= 10 u
Number of girls in Group B
= 14 u - 10 u
= 4 u
Fraction of the pupils in Group B that are girls
=
414=
27Answer(s):
27