At the movie theatre, child admission is$5.30 and adult admission is$9.50. On Tuesday, 165 tickets were sold for a total of $1265.10. How many child tickets were sold that day?

let a be the adult tickets and c be the child ticket.

1st equation: a + c = 165

2nd equation: 9.50a + 5.30c = 1265.10

Solve the 1st equation for a:

a + c = 165

a = 165 - c

Substitute a value from 1st equation to 2nd equation:

9.50a + 5.30c = 1265.10

9.50 (165 - c) + 5.30c = 1265.10

1567.5 - 9.5c + 5.30c = 1265.10

1567.5 - 1265.1 = 4.2c

302.4 = 4.2c

302.4/4.2 = c

72 = c

Answer: There were 72 child ticket sold.