Performance Tickets

[chetanojha]

Can somebody please explain the answer to me or point me to the link where this question has been discussed.

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For a recent play performance, the ticket prices were $25 per adult and $15 per child. A total of 500 tickets were sold for the performance. How many of the tickets sold were for adults?
(1) Revenue from ticket sales for this performance totaled $10,500.
(2) The average (arithmetic mean) price per ticket sold was $21.


OA: D

[shanrizvi]

Lets summarize/simplify the information given in the question first.

Total Revenue = 25a + 15c
a + c = 500

Statement 1: Total Revenue = 10,500

a + c = 500
25a + 15c = 10500

2 equations and 2 variables. Solve for a and c. SUFFICIENT.

Statement 2: Average price per ticket = 21

Average price = Total Revenue/Total Number of People
21 = Total Revenue/500
Total Revenue = 10500

Same as Statement 1. Hence, SUFFICIENT.

Answer: D