Fill in the blanks.
Number of girls at first is 20% of the children.
Number of girls is then increased to 70%.
- Number of girls at first = _____ u
- Number of girls in the end = _____ u
- Increase in the number of girls = _____ u
- Number of children in the end = _____ u
|
Girls |
Boys |
Before |
1 x 3 = 3 u |
4 x 3 = 12 u |
Change |
+ ? |
No change |
After |
7 x 4 = 28 u |
3 x 4 = 12 u |
(a)
Change percentage into units.
20% =
20100 =
15 70% =
70100 =
710 Fraction of the children who are boys at first
= 1 -
15 =
45 Fraction of the children who are boys in the end
= 1 -
710=
310 Number of boys at first and in the end remains the same.
The number of boys is the unchanged quantity.
LCM of 4 and 3 = 12
Number of girls at first = 3 u
(b)
Number of girls in the end = 28 u
(c)
Increase in the number of girls
= 28 u - 3 u
= 25 u
(d)
Number of children in the end
= 28 u + 12 u
= 40 u
Answer(s): (a) 3; (b) 28; (c) 25; (d) 40