There are thrice as many children as adults in a concert hall. There are 150 more boys than girls. If there are 448 people in the concert hall,
- how many children are there?
- how many girls are there?
- how many boys are there?
| Children |
Adults |
Total |
| 3 u |
1 u |
4 u |
| Girls |
Boys |
|
|
| 1 p |
1 p + 150 |
|
|
(a)
Number of adults = 1 u
Number of children = 3 x 1 u = 3 u
Total number of people
= 3 u + 1 u
= 4 u
4 u = 448
1 u = 448 ÷ 4 = 112
(a)
Number of children
= 3 u
= 3 x 112
= 336
(b)
Number of girls = 1 p
Number of boys = 1 p + 150
1 p + 1 p + 150 = 336
2 p + 150 = 336
2 p = 336 - 150
2 p = 186
1 p = 186 ÷ 2 = 93
Number of girls
= 1 p
= 93
(c)
Number of boys
= 1 p + 150
= 93 + 150
= 243
Answer(s): (a) 336; (b) 93; (c) 243
