There are 90 people,
of which 20 are boys.
There are 40 more adults than girls.
- How many adults are there?
- How many children are there?
- How many more adults than children are there?
- How many less girls than boys are there?
(a)
Number of boys = 20
Number of girls = 1 u
Number of adults = 1 u + 40
Total number of people
= 20 + 1 u + 1 u + 40
= 1 u + 1 u + 20 + 40
= 2 u + 60
2 u + 60 = 90
2 u = 90 - 60
2 u = 30
1 u = 30 ÷ 2 = 15
Number of adults
= 1 u + 40
= 15 + 40
= 55
(b)
Number of children
= 20 + 15
= 35
(c)
Number of more adults than children
= 55 - 35
= 20
(d)
Number of less girls than boys
= 20 - 15
= 5
Answer(s): (a) 55; (b) 35; (c) 20; (d) 5