Fill in the blanks.
The ratio of the number of girls to the number of boys in Class A is 3 : 2.
The ratio of the number of girls to the number of boys in Class B is 7 : 9.
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 |
3 x 7 |
2 x 7 |
7 x 3 |
9 x 3 |
21 u |
14 u |
21 u |
27 u |
Change ratio into units.
The number of girls in Class A and Class B is the same.
LCM of 3 and 7 = 21
Number of children in Class A
= 21 u + 14 u
= 35 u
Number of children in Class B
= 21 u + 27 u
= 48 u
Difference in the number of children in Class A and Class B
= 48 u - 35 u
= 13 u
(b)
Number of boys in Class A = 14 u
Number of boys in Class B = 27 u
Difference in the number of boys in Class A and Class B
= 27 u - 14 u
= 13 u
(c)
Number of girls in Class A = 21 uNumber of girls in Class B = 21 u Total number of girls = 21 u + 21 u= 42 u (d)
Total number of boys in Class A and Class B
= 27 u + 14 u
= 41 u
Answer(s)
: (a) 13; (b) 13; (c) 42; (d) 41