Fill in the blanks.
The ratio of the number of boys to the number of girls in Class A is 8 : 5.
The ratio of the number of boys to the number of girls in Class B is 3 : 10.
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 |
8 x 3 |
5 x 3 |
3 x 8 |
10 x 8 |
24 u |
15 u |
24 u |
80 u |
(a)
Change ratio into units.
The number of boys in Class A and Class B is the same.
LCM of 8 and 3 = 24
Class A
Boys : Girls
8 : 5
(x3) 24 : 15
Class B
Boys : Girls
3 : 10
(x8) 24 : 80
Number of boys in Class A = 24 u
(b)
Number of girls in Class B = 80 u
(c)
Number of children in Class B
= 24 u + 80 u
= 104 u
(d)
Number of children in Class A
= 24 u + 15 u
= 39 u
Total number of children
= 104 u + 39 u
= 143 u
Answer(s): (a) 24; (b) 80; (c) 104; (d) 143