Answer:
The number of children at the pool that day is 313
The number of adults at the pool that day is 296
Explanation:
Given as :
The Total number of people were using public pool = 609
The Total admission receipt collected at the day end = $1061.50
The entry price for children = $1.50
The entry price for adults = $2.00
Let The total number of children in the pool = c
And The total number of adults in the pool = a
Now, According to question
The Total number of people were using public pool = The total number of children in the pool + The total number of adults in the pool
or, c + a = 609 ...........1
And
The Total admission receipt collected at the day end = The entry price for children × The total number of children in the pool + The entry price for adults × The total number of adults in the pool
or, $1.50 × c + $2.00 × a = $1061.50
I.e 1.50 c + 2 a = 1061.50 ............2
Now, Solving equation 1 and 2
2 × (c + a) - (1.50 c + 2 a) = 2 × 609 - 1061.50
Or, 2 c + 2 a - 1.50 c - 2 a = 1218 - 1061.50
Or, (2 c - 1.50 c) + (2 a - 2 a) = 156.5
Or, 0.5 c + 0 = 156.5
∴ c =

I.e c = 313
So, The number of children at the pool = c = 313
Now,
Put The value of c in eq 1
I.e ,c + a = 609
Or, 313 + a = 609
Or, a = 609 - 313
∴ a = 296
So, The number of adults at the pool = a = 296
Hence The number of children at the pool that day is 313
And The number of adults at the pool that day is 296 Answer