Some visitors paid a total of $510 for entrance tickets to a theme park. The entrance ticket for a child cost $3. The entrance ticket for an adult cost 4 times as much. If there were 20 more adults than children, how many of the visitors were
- children?
- adults?
|
Adults |
Children |
Total |
Number |
1 u + 20 |
1 u |
|
Value |
$12 |
$3 |
|
Total value |
12 u + 240 |
3 u |
$510 |
(a)
Cost of an adult ticket
= 4 x 3
= $12
Cost of all the adult tickets
= 12(1 u + 20)
= 12 u + 240
Total cost of the tickets
= 12 u + 240 + 3 u
= 15 u + 240
15 u + 240 = 510
15 u = 510 - 240
15 u = 270
1 u = 270 ÷ 15 = 18
Total number of children
= 1 u
= 18
(b)
Total number of adults
= 1 u + 20
= 18 + 20
= 38
Answer(s): (a) 18; (b) 38