Fill in the blanks.
The ratio of the number of boys to the number of girls in Class A is 6 : 5.
The ratio of the number of boys to the number of girls in Class B is 7 : 9.
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 |
6 x 7 |
5 x 7 |
7 x 6 |
9 x 6 |
42 u |
35 u |
42 u |
54 u |
(a)
Change ratio into units.
The number of boys in Class A and Class B is the same.
LCM of 6 and 7 = 42
Class A
Boys : Girls
6 : 5
(x7) 42 : 35
Class B
Boys : Girls
7 : 9
(x6) 42 : 54
Number of boys in Class A = 42 u
(b)
Number of girls in Class B = 54 u
(c)
Number of children in Class B
= 42 u + 54 u
= 96 u
(d)
Number of children in Class A
= 42 u + 35 u
= 77 u
Total number of children
= 96 u + 77 u
= 173 u
Answer(s): (a) 42; (b) 54; (c) 96; (d) 173