Question

The admission fee at a movie theater is $2.50 for children and $7.00 for adults. On a certain day, 2100 people enter the theater and $7950 is collected. How many children and how many adults attended

Answer 1

Make two equations
C = children, A = adults
2.50C + 7.00A = 7950
(C + A = 2100) * 2.5
2.50C + 2.50A = 5250
Use elimination
4.5A = 2700, A = 600
2100 - 600 = 1500
Solution: 600 adults, 1500 children