Fill in the blanks.
The ratio of the number of boys to the number of girls in Class A is 3 : 2.
The ratio of the number of boys to the number of girls in Class B is 2 : 5.
The number of boys is the same.
- Number of boys in Class A = _____ u
- Number of girls in Class B = _____ u
- Number of children in Class B = _____ u
- Total number of children = _____ u
Class A |
Class B |
Boys |
Girls |
Boys |
Girls |
3 x 2 |
2 x 2 |
2 x 3 |
5 x 3 |
6 u |
4 u |
6 u |
15 u |
(a)
Change ratio into units.
The number of boys in Class A and Class B is the same.
LCM of 3 and 2 = 6
Class A
Boys : Girls
3 : 2
(x2) 6 : 4
Class B
Boys : Girls
2 : 5
(x3) 6 : 15
Number of boys in Class A = 6 u
(b)
Number of girls in Class B = 15 u
(c)
Number of children in Class B
= 6 u + 15 u
= 21 u
(d)
Number of children in Class A
= 6 u + 4 u
= 10 u
Total number of children
= 21 u + 10 u
= 31 u
Answer(s): (a) 6; (b) 15; (c) 21; (d) 31