There are 80 people,
of which 20 are boys.
There are 30 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 + 30
Total number of people
= 20 + 1 u + 1 u + 30
= 1 u + 1 u + 20 + 30
= 2 u + 50
2 u + 50 = 80
2 u = 80 - 50
2 u = 30
1 u = 30 ÷ 2 = 15
Number of adults
= 1 u + 30
= 15 + 30
= 45
(b)
Number of children
= 20 + 15
= 35
(c)
Number of more adults than children
= 45 - 35
= 10
(d)
Number of less girls than boys
= 20 - 15
= 5
Answer(s): (a) 45; (b) 35; (c) 10; (d) 5