There are 60 people,
of which 10 are boys.
There are 30 less adults than girls.
- How many adults are there?
- How many children are there?
- How many less adults than children are there?
- How many more girls than boys are there?
(a)
Number of boys = 10
Number of adults = 1 u
Number of girls = 1 u + 30
Total number of people
= 10 + 1 u + 1 u + 30
= 1 u + 1 u + 10 + 30
= 2 u + 40
2 u + 40 = 60
2 u = 60 - 40
2 u = 20
1 u = 20 ÷ 2 = 10
Number of adults
= 1 u
= 10
(b)
Number of children
= 10 + 1 u + 30
= 10 + 10 + 30
= 50
(c)
Number of less adults than children
= 50 - 10
= 40
(d)
Number of more girls than boys
= 1 u + 30 - 10
= 10 + 30 - 10
= 30
Answer(s): (a) 10; (b) 50; (c) 40; (d) 30