20% of the people are performers for a concert and the rest are spectators. 60% of the spectators are adults and there are 240 more adult spectators than child spectators. How many adult spectators must leave so that 35% of the people are adult spectators?
|
Performers |
Spectators |
|
1x5 |
4x5 |
|
|
Children |
Adults |
|
|
2x4 |
3x4 |
Before |
5 u |
8 u |
12 u |
Change |
|
|
- ? |
After |
13x1 = 13 u |
7x1 = 7 u |
20% =
20100 =
15 60% =
60100 =
35 35% =
35100 =
720The total number of spectators at first is repeated. Make the total number of spectators the same. LCM of 4 and 5 is 20.
Number of more adult spectators than child spectators at first
= 12 u - 8 u
= 4 u
4 u = 240
1 u = 240 ÷ 4 = 60
If some adult spectators leave, the total number of child spectators and performers remains unchanged.
Number of adult spectators who must leave so that 35% of the people are adult spectators
= 12 u - 7 u
= 5 u
= 5 x 60
= 300
Answer(s): 300