Fill in the blanks.
The ratio of the number of girls to the number of boys in Class A is 5 : 4.
The ratio of the number of girls to the number of boys in Class B is 2 : 5.
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 |
5 x 2 |
4 x 2 |
2 x 5 |
5 x 5 |
10 u |
8 u |
10 u |
25 u |
(a)
Change ratio into units.
The number of girls in Class A and Class B is the same.
LCM of 5 and 2 = 10
Class A
Girls : Boys
5 : 4
(x2) 10 : 8
Class B
Girls : Boys
2 : 5
(x5) 10 : 25
Number of girls in Class A = 10 u
(b)
Number of boys in Class B = 25 u
(c)
Number of children in Class B
= 10 u + 25 u
= 35 u
(d)
Number of children in Class A
= 10 u + 8 u
= 18 u
Total number of children
= 35 u + 18 u
= 53 u
Answer(s): (a) 10; (b) 25; (c) 35; (d) 53