Fill in the blanks.
The ratio of the number of boys to the number of girls in Class A is 3 : 1.
The ratio of the number of boys to the number of girls in Class B is 5 : 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 |
3 x 5 |
1 x 5 |
5 x 3 |
7 x 3 |
15 u |
5 u |
15 u |
21 u |
Change ratio into units.
The number of boys in Class A and Class B is the same.
LCM of 3 and 5 = 15
Number of children in Class A
= 15 u + 5 u
= 20 u
Number of children in Class B
= 15 u + 21 u
= 36 u
Difference in the number of children in Class A and Class B
= 36 u - 20 u
= 16 u
(b)
Number of girls in Class A = 5 u
Number of girls in Class B = 21 u
Difference in the number of girls in Class A and Class B
= 21 u - 5 u
= 16 u
(c)
Number of boys in Class A = 15 uNumber of boys in Class B = 15 u Total number of boys = 15 u + 15 u= 30 u (d)
Total number of girls in Class A and Class B
= 21 u + 5 u
= 26 u
Answer(s)
: (a) 16; (b) 16; (c) 30; (d) 26