Question 971547
X=children 
(3/4)x=teenagers
570-(7/4)x=adults 

2x+(3/4)x*3+5*(570-(7/4)x=1950.  The adults are the total minus the sum of the other 2 groups. 

-(18/4)x +2850 = 1950

-(18/4)x = -900

Change both signs and multiply both by 4

18x = 3600
X=200. Children 
.75x=150 teenagers 
220= adults



Revenue in order is
400
450
1100.  = 1950