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 8 : 9.
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 4 |
7 x 4 |
8 x 5 |
9 x 5 |
40 u |
28 u |
40 u |
45 u |
Change ratio into units.
The number of boys in Class A and Class B is the same.
LCM of 10 and 8 = 40
Number of children in Class A
= 40 u + 28 u
= 68 u
Number of children in Class B
= 40 u + 45 u
= 85 u
Difference in the number of children in Class A and Class B
= 85 u - 68 u
= 17 u
(b)
Number of girls in Class A = 28 u
Number of girls in Class B = 45 u
Difference in the number of girls in Class A and Class B
= 45 u - 28 u
= 17 u
(c)
Number of boys in Class A = 40 uNumber of boys in Class B = 40 u Total number of boys = 40 u + 40 u= 80 u (d)
Total number of girls in Class A and Class B
= 45 u + 28 u
= 73 u
Answer(s)
: (a) 17; (b) 17; (c) 80; (d) 73