Fill in the blanks.
Number of boys at first is 20% of the children.
Number of boys is then increased to 35%.
- 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 13 = 13 u |
4 x 13 = 52 u |
Change |
+ ? |
No change |
After |
7 x 4 = 28 u |
13 x 4 = 52 u |
(a)
Change percentage into units.
20% =
20100 =
15 35% =
35100 =
720 Fraction of the children who are girls at first
= 1 -
15 =
45 Fraction of the children who are girls in the end
= 1 -
720=
1320 Number of girls at first and in the end remains the same.
The number of girls is the unchanged quantity.
LCM of 4 and 13 = 52
Number of boys at first = 13 u
(b)
Number of boys in the end = 28 u
(c)
Increase in the number of boys
= 28 u - 13 u
= 15 u
(d)
Number of children in the end
= 28 u + 52 u
= 80 u
Answer(s): (a) 13; (b) 28; (c) 15; (d) 80