The theatre had 2025 seats. There were 20% fewer $25-seats than $20-seats. 60% of the $20-seats and some $25-seats were sold. A total of $22175 was collected. How many seats were unsold?

	$25	$20	Total
Number	4 u	5 u	9 u

100% - 20% = 80%
⁸⁰₁₀₀ = ⁴₅

Total number of seats
= 4 u + 5 u
= 9 u

9 u = 2025

1 u = 2025 ÷ 9 = 225

Total number of $20-seat tickets
= 5 u
= 5 x 225
= 1125

Number of $20-seat tickets sold
= 60% x 1125
= ⁶⁰₁₀₀ x 1125
= 675

Amount collected from $20-seat tickets sold
= 675 x 20
= $13500

Amount collected from $25-seat tickets sold
= 22175 - 13500
= $8675

Number of $25-seat tickets sold
= 8675 ÷ 25
= 347

Number of tickets sold
= 675 + 347
= 1022

Number of tickets left unsold
= 2025 - 1022
= 1003

Answer(s): 1003