Fill in the blanks.
The ratio of the number of boys to the number of girls in Class A is 5 : 1.
The ratio of the number of boys to the number of girls in Class B is 7 : 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 |
5 x 7 |
1 x 7 |
7 x 5 |
10 x 5 |
35 u |
7 u |
35 u |
50 u |
(a)
Change ratio into units.
The number of boys in Class A and Class B is the same.
LCM of 5 and 7 = 35
Class A
Boys : Girls
5 : 1
(x7) 35 : 7
Class B
Boys : Girls
7 : 10
(x5) 35 : 50
Number of boys in Class A = 35 u
(b)
Number of girls in Class B = 50 u
(c)
Number of children in Class B
= 35 u + 50 u
= 85 u
(d)
Number of children in Class A
= 35 u + 7 u
= 42 u
Total number of children
= 85 u + 42 u
= 127 u
Answer(s): (a) 35; (b) 50; (c) 85; (d) 127