Answer:
153 children, 135 adults
Explanation:
Let a represent the number of children
Let b represent the number of adults
a+b=288------equation 1
Since the daily price for children is $1.75 and the price for adults is $2.25. Then equation 2 can be expressed as
1.75a+2.25b=571.50-----equation 2
From equation 1
a+b=288
a=288-b
Substitute (288-b) for a in equation 2
1.75(288-b) +2.25b=571.50
504-1.75b+2.25b=571.50
Collect the like terms
-1.75b+2.25b= 571.50-504
0.5b=67.5
Divide both sides by the coefficient of b which is 0.5
0.5b/0.5=67.5/0.5
b= 135
Substitute 135 for b in equation 1
a+b=288
a+135=288
a=288-135
a= 153
Hence 153 children and 135 adults swam at the pool