Nathan B. answered 04/02/18
Tutor
5
(20)
Elementary and Algebraic skilled
Here's what we know:
a + d = 684 (attendance and door tickets equal 684 sold)
3a + 4d = 2457 (total ticket proceeds equals $2457)
Let's solve this through elimination. Multiply the first equation by -3:
-3a - 3d = -2052
3a + 4d = 2457
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d = 405
Now that you know the door tickets, you can use that to find how many advance tickets were sold.