Fill in the blanks.
The ratio of the number of girls to the number of boys in Class A is 7 : 3.
The ratio of the number of girls to the number of boys in Class B is 2 : 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 |
7 x 2 |
3 x 2 |
2 x 7 |
7 x 7 |
14 u |
6 u |
14 u |
49 u |
Change ratio into units.
The number of girls in Class A and Class B is the same.
LCM of 7 and 2 = 14
Number of children in Class A
= 14 u + 6 u
= 20 u
Number of children in Class B
= 14 u + 49 u
= 63 u
Difference in the number of children in Class A and Class B
= 63 u - 20 u
= 43 u
(b)
Number of boys in Class A = 6 u
Number of boys in Class B = 49 u
Difference in the number of boys in Class A and Class B
= 49 u - 6 u
= 43 u
(c)
Number of girls in Class A = 14 uNumber of girls in Class B = 14 u Total number of girls = 14 u + 14 u= 28 u (d)
Total number of boys in Class A and Class B
= 49 u + 6 u
= 55 u
Answer(s)
: (a) 43; (b) 43; (c) 28; (d) 55