Let's assume the number of child tickets sold is represented by 'C' and the number of adult tickets sold is represented by 'A'.
From the given information, we can set up the following equations:
1. C + A = 146 (equation representing the total number of tickets sold)
2. 5.70C + 9.30A = 1015.80 (equation representing the total sales)
To solve this system of equations, we can use substitution or elimination. Let's use the substitution method.
From equation 1, we have C = 146 - A.
Substituting this value of C into equation 2, we get:
5.70(146 - A) + 9.30A = 1015.80
Expanding and simplifying:
832.20 - 5.70A + 9.30A = 1015.80
Combine like terms:
3.60A = 183.60
Divide both sides by 3.60:
A = 51
Substituting this value of A back into equation 1, we find:
C + 51 = 146
C = 146 - 51
C = 95
Therefore, 95 child tickets were sold on that day.