10% of the people are performers for a concert and the rest are spectators. 80% of the spectators are children and there are 1350 more child spectators than parent spectators. How many child spectators must leave so that 30% of the people are child spectators?
|
Performers |
Spectators |
|
1x5 |
9x5 |
|
|
Parents |
Children |
|
|
1x9 |
4x9 |
Before |
5 u |
9 u |
36 u |
Change |
|
|
- ? |
After |
7x2 = 14 u |
3x2 = 6 u |
10% =
10100 =
110 80% =
80100 =
45 30% =
30100 =
310The total number of spectators at first is repeated. Make the total number of spectators the same. LCM of 9 and 5 is 45.
Number of more child spectators than parent spectators at first
= 36 u - 9 u
= 27 u
27 u = 1350
1 u = 1350 ÷ 27 = 50
If some child spectators leave, the total number of parent spectators and performers remains unchanged.
Number of child spectators who must leave so that 30% of the people are child spectators
= 36 u - 6 u
= 30 u
= 30 x 50
= 1500
Answer(s): 1500