The theatre had 1029 seats. There were 25% fewer $35-seats than $5-seats. 75% of the $5-seats and some $35-seats were sold. A total of $17430 was collected. How many seats were unsold?

	$35	$5	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 = 1029

1 u = 1029 ÷ 7 = 147

Total number of $5-seat tickets
= 4 u
= 4 x 147
= 588

Number of $5-seat tickets sold
= 75% x 588
= ⁷⁵₁₀₀ x 588
= 441

Amount collected from $5-seat tickets sold
= 441 x 5
= $2205

Amount collected from $35-seat tickets sold
= 17430 - 2205
= $15225

Number of $35-seat tickets sold
= 15225 ÷ 35
= 435

Number of tickets sold
= 441 + 435
= 876

Number of tickets left unsold
= 1029 - 876
= 153

Answer(s): 153