There are 100 people,
of which 20 are girls.
There are 70 more adults than boys.
- How many adults are there?
- How many children are there?
- How many more adults than children are there?
- How many less boys than girls are there?
(a)
Number of girls = 20
Number of boys = 1 u
Number of adults = 1 u + 70
Total number of people
= 20 + 1 u + 1 u + 70
= 1 u + 1 u + 20 + 70
= 2 u + 90
2 u + 90 = 100
2 u = 100 - 90
2 u = 10
1 u = 10 ÷ 2 = 5
Number of adults
= 1 u + 70
= 5 + 70
= 75
(b)
Number of children
= 20 + 5
= 25
(c)
Number of more adults than children
= 75 - 25
= 50
(d)
Number of less boys than girls
= 20 - 5
= 15
Answer(s): (a) 75; (b) 25; (c) 50; (d) 15