The symphony sells two kinds of tickets: orchestra, for $30, and upper tiers, for $12. On a certain night, the symphony sells 90 tickets and gets $1926 in revenue from the sales. How many orchestra tickets did they sell?  Choose the correct option.
A) 35	B) 39	C) 43	D) 47	E) 51
Let x be the number of orchestra tickets.   Then 90-x is the number of upper tier tickets.   30x + 12(90-x) = 1926   18x = 1926-1080   x = 47   The answer is 47.
<result>D</result>
The symphony sells two kinds of tickets: orchestra, for $30, and upper tiers, for $12. On a certain night, the symphony sells 90 tickets and gets $1926 in revenue from the sales. How many orchestra tickets did they sell?