At a concert hall, each adult ticket cost $38 and each child ticket cost $9. On Thursday, the number of adult tickets sold was 140 less than the number of child tickets. On Friday, the number of adult tickets sold decreased by 15% while the number of child tickets sold increased by 25%. If a total of 1435 tickets were sold on Friday, how much money was collected on Thursday?

	Adult tickets	Child tickets	Total tickets
Before	1 u	1 u + 140	2 u + 140
Change	- 0.15 u	+ 0.25 u + 35
After	0.85 u	1.25 u + 175	2.1 u + 175

15% x 1 u = ¹⁵₁₀₀ x 1 u = 0.15 u 
25% x 1 u = ²⁵₁₀₀ x 1 u = 0.25 u
25% x 140 = ²⁵₁₀₀ x 140 = 35

Number of tickets sold on Friday
= 0.85 u + 1.25 u + 175
= 2.1 u + 175

2.1 u + 175 = 1435
2.1 u = 1435 - 175
2.1 u = 1260

1 u = 1260 ÷ 2.1 = 600

Amount collected from adult tickets on Thursday
= 1 u x 38
= 600 x 38
= $22800

Amount collected from child tickets on Thursday
= 9(1 u + 140)
= 9(600 + 140)
= 9 x 740
= $6660

Total amount collected on Thursday
= 22800 + 6660
= $29460

Answer(s):$29460