Fill in the blanks.
The ratio of the number of girls to the number of boys in Class A is 4 : 3.
The ratio of the number of girls to the number of boys in Class B is 3 : 10.
The number of girls is the same.
- Number of girls in Class A = _____ u
- Number of boys in Class B = _____ u
- Number of children in Class B = _____ u
- Total number of children = _____ u
Class A |
Class B |
Girls |
Boys |
Girls |
Boys |
4 x 3 |
3 x 3 |
3 x 4 |
10 x 4 |
12 u |
9 u |
12 u |
40 u |
(a)
Change ratio into units.
The number of girls in Class A and Class B is the same.
LCM of 4 and 3 = 12
Class A
Girls : Boys
4 : 3
(x3) 12 : 9
Class B
Girls : Boys
3 : 10
(x4) 12 : 40
Number of girls in Class A = 12 u
(b)
Number of boys in Class B = 40 u
(c)
Number of children in Class B
= 12 u + 40 u
= 52 u
(d)
Number of children in Class A
= 12 u + 9 u
= 21 u
Total number of children
= 52 u + 21 u
= 73 u
Answer(s): (a) 12; (b) 40; (c) 52; (d) 73