The drama centre had 2037 seats. There were 25% fewer $50-seats than $10-seats. 50% of the $10-seats and some $50-seats were sold. A total of $30320 was collected. How many seats were unsold?

	$50	$10	Total
Number	3 u	4 u	7 u

100% - 25% = 75%
⁷⁵₁₀₀ = ³₄

Total number of seats
= 3 u + 4 u
= 7 u

7 u = 2037

1 u = 2037 ÷ 7 = 291

Total number of $10-seat tickets
= 4 u
= 4 x 291
= 1164

Number of $10-seat tickets sold
= 50% x 1164
= ⁵⁰₁₀₀ x 1164
= 582

Amount collected from $10-seat tickets sold
= 582 x 10
= $5820

Amount collected from $50-seat tickets sold
= 30320 - 5820
= $24500

Number of $50-seat tickets sold
= 24500 ÷ 50
= 490

Number of tickets sold
= 582 + 490
= 1072

Number of tickets left unsold
= 2037 - 1072
= 965

Answer(s): 965