The auditorium had 1024 seats. There were 40% fewer $30-seats than $20-seats. 75% of the $20-seats and some $30-seats were sold. A total of $19050 was collected. How many seats were unsold?

	$30	$20	Total
Number	3 u	5 u	8 u

100% - 40% = 60%
⁶⁰₁₀₀ = ³₅

Total number of seats
= 3 u + 5 u
= 8 u

8 u = 1024

1 u = 1024 ÷ 8 = 128

Total number of $20-seat tickets
= 5 u
= 5 x 128
= 640

Number of $20-seat tickets sold
= 75% x 640
= ⁷⁵₁₀₀ x 640
= 480

Amount collected from $20-seat tickets sold
= 480 x 20
= $9600

Amount collected from $30-seat tickets sold
= 19050 - 9600
= $9450

Number of $30-seat tickets sold
= 9450 ÷ 30
= 315

Number of tickets sold
= 480 + 315
= 795

Number of tickets left unsold
= 1024 - 795
= 229

Answer(s): 229