Question

Six hundred people attended the premiere of a motion pic. Adult cost $13, and children were admitted for $2. If box office receipts totaled $2630, how many children attended the premiere?

Answer 1

470

Explanation:

Let a be adult at premiere.

Let c be children at premiere.

Equation 1:- a + c = 600

Let 13a be total price of tickets for adults.

Let 2c be total price of tickets for children.

Equation 2:- 13a + 2c = 2630

Solve simultaneously for c to determine children at premiere.

Make c the subject from Equation 1 to get Equation 3.

Equation 3:- c = 600 - a

Substitute c's value in Equation 3 in Equation 2

13a + 2 (600 - a) = 2630

13a + 1200 -2a = 2630

11a = 2630 -1200

11a = 1430

a = 130

Substitute value of a in Equation 3

c = 600 - 130

c = 470