Fill in the blanks.
The ratio of the number of boys to the number of girls in Class A is 10 : 7.
The ratio of the number of boys to the number of girls in Class B is 3 : 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 |
10 x 3 |
7 x 3 |
3 x 10 |
7 x 10 |
30 u |
21 u |
30 u |
70 u |
Change ratio into units.
The number of boys in Class A and Class B is the same.
LCM of 10 and 3 = 30
Number of children in Class A
= 30 u + 21 u
= 51 u
Number of children in Class B
= 30 u + 70 u
= 100 u
Difference in the number of children in Class A and Class B
= 100 u - 51 u
= 49 u
(b)
Number of girls in Class A = 21 u
Number of girls in Class B = 70 u
Difference in the number of girls in Class A and Class B
= 70 u - 21 u
= 49 u
(c)
Number of boys in Class A = 30 uNumber of boys in Class B = 30 u Total number of boys = 30 u + 30 u= 60 u (d)
Total number of girls in Class A and Class B
= 70 u + 21 u
= 91 u
Answer(s)
: (a) 49; (b) 49; (c) 60; (d) 91