Fill in the blanks.
The ratio of the number of girls to the number of boys in Class A is 5 : 3.
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 |
5 x 7 |
3 x 7 |
7 x 5 |
9 x 5 |
35 u |
21 u |
35 u |
45 u |
Change ratio into units.
The number of girls in Class A and Class B is the same.
LCM of 5 and 7 = 35
Number of children in Class A
= 35 u + 21 u
= 56 u
Number of children in Class B
= 35 u + 45 u
= 80 u
Difference in the number of children in Class A and Class B
= 80 u - 56 u
= 24 u
(b)
Number of boys in Class A = 21 u
Number of boys in Class B = 45 u
Difference in the number of boys in Class A and Class B
= 45 u - 21 u
= 24 u
(c)
Number of girls in Class A = 35 uNumber of girls in Class B = 35 u Total number of girls = 35 u + 35 u= 70 u (d)
Total number of boys in Class A and Class B
= 45 u + 21 u
= 66 u
Answer(s)
: (a) 24; (b) 24; (c) 70; (d) 66