There were an equal number of boys in Class 1R and Class 1S.
45 of the students in Class 1R are boys and
19 of the students in Class 1S are girls. Given that there are a total of 12 girls in the two classes, how many students are there in Class 1S?
| Class 1R |
Class 1S |
| Boys |
Girls |
Boys |
Girls |
| 4x2 |
1x2 |
8 |
1 |
| 8 u |
2 u |
8 u |
1 u |
Fraction of boys in Class 1S
= 1 -
19=
89The number of boys in Class 1R and Class 1S is the same. Make the numerators the same.
4x25x2 of students in Class 1R =
89 of students in Class 1S
810 of students in Class 1R =
89 of students in Class 1S
Total number of girls
= 2 u + 1 u
= 3 u
3 u = 12
1 u = 12 ÷ 3 = 4
Number of students in Class 1S
= 9 u
= 9 x 4
= 36
Answer(s): 36
