Fill in the blanks.
The ratio of the number of girls to the number of boys in Class A is 9 : 2.
The ratio of the number of girls to the number of boys in Class B is 5 : 7.
The number of girls is the same.
- Difference in the number of children in Class A and Class B = _____ u
- Difference in the number of boys in Class A and Class B = _____ u
- Total number of girls = _____ u
- Total number of boys = _____ u
(a)
Class A |
Class B |
Girls |
Boys |
Girls |
Boys |
9 x 5 |
2 x 5 |
5 x 9 |
7 x 9 |
45 u |
10 u |
45 u |
63 u |
Change ratio into units.
The number of girls in Class A and Class B is the same.
LCM of 9 and 5 = 45
Number of children in Class A
= 45 u + 10 u
= 55 u
Number of children in Class B
= 45 u + 63 u
= 108 u
Difference in the number of children in Class A and Class B
= 108 u - 55 u
= 53 u
(b)
Number of boys in Class A = 10 u
Number of boys in Class B = 63 u
Difference in the number of boys in Class A and Class B
= 63 u - 10 u
= 53 u
(c)
Number of girls in Class A = 45 uNumber of girls in Class B = 45 u Total number of girls = 45 u + 45 u= 90 u (d)
Total number of boys in Class A and Class B
= 63 u + 10 u
= 73 u
Answer(s)
: (a) 53; (b) 53; (c) 90; (d) 73