There are 100 people,
of which 10 are girls.
There are 80 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 = 10
Number of boys = 1 u
Number of adults = 1 u + 80
Total number of people
= 10 + 1 u + 1 u + 80
= 1 u + 1 u + 10 + 80
= 2 u + 90
2 u + 90 = 100
2 u = 100 - 90
2 u = 10
1 u = 10 ÷ 2 = 5
Number of adults
= 1 u + 80
= 5 + 80
= 85
(b)
Number of children
= 10 + 5
= 15
(c)
Number of more adults than children
= 85 - 15
= 70
(d)
Number of less boys than girls
= 10 - 5
= 5
Answer(s): (a) 85; (b) 15; (c) 70; (d) 5