Tickets to the zoo cost $4 for children, $5 for teenagers and $6 for adults. In the high season, 1200 people come to the zoo every day. On a certian day, the total revenue at the zoo was $5300. For every 3 teenagers, 8 children went to the zoo. How many adults went to the zoo?

a.

100 adults

c.

200 adults

b.

150 adults

d.

250 adults

C/t=8/3, c=8t/3

a+c+t=1200, using c from above:

a+8t/3 + t = 1200

3a+8t+3t=3600

11t+3a=3600

t = (3600-3a) / 11 and from earlier we said c=8t/3, and using this with t we just found:

c = (28800-24a) / 33

5300=6a+5t+4c, using c and t from earlier

5300=6a + (18000-15a) / 11 + (115200-96a) / 33 make the common denominator 33 ...

174900=198a+54000-45a+115200-96a

57a=5700

a=100

So 100 adult tickets were sold.