Fill in the blanks.
Number of boys at first is 20% of the children.
Number of boys is then increased to 55%.
- Number of boys at first = _____ u
- Number of boys in the end = _____ u
- Increase in the number of boys = _____ u
- Number of children in the end = _____ u
|
Boys |
Girls |
Before |
1 x 9 = 9 u |
4 x 9 = 36 u |
Change |
+ ? |
No change |
After |
11 x 4 = 44 u |
9 x 4 = 36 u |
(a)
Change percentage into units.
20% =
20100 =
15 55% =
55100 =
1120 Fraction of the children who are girls at first
= 1 -
15 =
45 Fraction of the children who are girls in the end
= 1 -
1120=
920 Number of girls at first and in the end remains the same.
The number of girls is the unchanged quantity.
LCM of 4 and 9 = 36
Number of boys at first = 9 u
(b)
Number of boys in the end = 44 u
(c)
Increase in the number of boys
= 44 u - 9 u
= 35 u
(d)
Number of children in the end
= 44 u + 36 u
= 80 u
Answer(s): (a) 9; (b) 44; (c) 35; (d) 80