Fill in the blanks.
The ratio of the number of boys to the number of girls in Class A is 9 : 5.
The ratio of the number of boys to the number of girls in Class B is 2 : 7.
The number of boys is the same.
- Difference in the number of children in Class A and Class B = _____ u
- Difference in the number of girls in Class A and Class B = _____ u
- Total number of boys = _____ u
- Total number of girls = _____ u
(a)
Class A |
Class B |
Boys |
Girls |
Boys |
Girls |
9 x 2 |
5 x 2 |
2 x 9 |
7 x 9 |
18 u |
10 u |
18 u |
63 u |
Change ratio into units.
The number of boys in Class A and Class B is the same.
LCM of 9 and 2 = 18
Number of children in Class A
= 18 u + 10 u
= 28 u
Number of children in Class B
= 18 u + 63 u
= 81 u
Difference in the number of children in Class A and Class B
= 81 u - 28 u
= 53 u
(b)
Number of girls in Class A = 10 u
Number of girls in Class B = 63 u
Difference in the number of girls in Class A and Class B
= 63 u - 10 u
= 53 u
(c)
Number of boys in Class A = 18 uNumber of boys in Class B = 18 u Total number of boys = 18 u + 18 u= 36 u (d)
Total number of girls in Class A and Class B
= 63 u + 10 u
= 73 u
Answer(s)
: (a) 53; (b) 53; (c) 36; (d) 73