At a stadium, each adult ticket cost $23 and each child ticket cost $7. On Friday, the number of adult tickets sold was 158 less than the number of child tickets. On Saturday, the number of adult tickets sold decreased by 10% while the number of child tickets sold increased by 50%. If a total of 1917 tickets were sold on Saturday, how much money was collected on Friday?

	Adult tickets	Child tickets	Total tickets
Before	1 u	1 u + 158	2 u + 158
Change	- 0.1 u	+ 0.5 u + 79
After	0.9 u	1.5 u + 237	2.4 u + 237

10% x 1 u = ¹⁰₁₀₀ x 1 u = 0.1 u 
50% x 1 u = ⁵⁰₁₀₀ x 1 u = 0.5 u
50% x 158 = ⁵⁰₁₀₀ x 158 = 79

Number of tickets sold on Saturday
= 0.9 u + 1.5 u + 237
= 2.4 u + 237

2.4 u + 237 = 1917
2.4 u = 1917 - 237
2.4 u = 1680

1 u = 1680 ÷ 2.4 = 700

Amount collected from adult tickets on Friday
= 1 u x 23
= 700 x 23
= $16100

Amount collected from child tickets on Friday
= 7(1 u + 158)
= 7(700 + 158)
= 7 x 858
= $6006

Total amount collected on Friday
= 16100 + 6006
= $22106

Answer(s):$22106