There are 630 people,
of which 30 are girls.
There are 120 less adults than boys.
- How many adults are there?
- How many children are there?
- How many less adults than children are there?
- How many more boys than girls are there?
(a)
Number of girls = 30
Number of adults = 1 u
Number of boys = 1 u + 120
Total number of people
= 30 + 1 u + 1 u + 120
= 1 u + 1 u + 30 + 120
= 2 u + 150
2 u + 150 = 630
2 u = 630 - 150
2 u = 480
1 u = 480 ÷ 2 = 240
Number of adults
= 1 u
= 240
(b)
Number of children
= 30 + 1 u + 120
= 30 + 240 + 120
= 390
(c)
Number of less adults than children
= 390 - 240
= 150
(d)
Number of more boys than girls
= 1 u + 120 - 30
= 240 + 120 - 30
= 330
Answer(s): (a) 240; (b) 390; (c) 150; (d) 330