At a museum, each adult ticket cost $29 and each child ticket cost $15. On Friday, the number of adult tickets sold was 130 less than the number of child tickets. On Saturday, the number of adult tickets sold decreased by 15% while the number of child tickets sold increased by 10%. If a total of 728 tickets were sold on Saturday, how much money was collected on Friday?

	Adult tickets	Child tickets	Total tickets
Before	1 u	1 u + 130	2 u + 130
Change	- 0.15 u	+ 0.1 u + 13
After	0.85 u	1.1 u + 143	1.95 u + 143

15% x 1 u = ¹⁵₁₀₀ x 1 u = 0.15 u 
10% x 1 u = ¹⁰₁₀₀ x 1 u = 0.1 u
10% x 130 = ¹⁰₁₀₀ x 130 = 13

Number of tickets sold on Saturday
= 0.85 u + 1.1 u + 143
= 1.95 u + 143

1.95 u + 143 = 728
1.95 u = 728 - 143
1.95 u = 585

1 u = 585 ÷ 1.95 = 300

Amount collected from adult tickets on Friday
= 1 u x 29
= 300 x 29
= $8700

Amount collected from child tickets on Friday
= 15(1 u + 130)
= 15(300 + 130)
= 15 x 430
= $6450

Total amount collected on Friday
= 8700 + 6450
= $15150

Answer(s):$15150