At a theme park, each adult ticket cost $35 and each child ticket cost $14. On Friday, the number of adult tickets sold was 65 less than the number of child tickets. On Saturday, the number of adult tickets sold decreased by 25% while the number of child tickets sold increased by 20%. If a total of 858 tickets were sold on Saturday, how much money was collected on Friday?

	Adult tickets	Child tickets	Total tickets
Before	1 u	1 u + 65	2 u + 65
Change	- 0.25 u	+ 0.2 u + 13
After	0.75 u	1.2 u + 78	1.95 u + 78

25% x 1 u = ²⁵₁₀₀ x 1 u = 0.25 u 
20% x 1 u = ²⁰₁₀₀ x 1 u = 0.2 u
20% x 65 = ²⁰₁₀₀ x 65 = 13

Number of tickets sold on Saturday
= 0.75 u + 1.2 u + 78
= 1.95 u + 78

1.95 u + 78 = 858
1.95 u = 858 - 78
1.95 u = 780

1 u = 780 ÷ 1.95 = 400

Amount collected from adult tickets on Friday
= 1 u x 35
= 400 x 35
= $14000

Amount collected from child tickets on Friday
= 14(1 u + 65)
= 14(400 + 65)
= 14 x 465
= $6510

Total amount collected on Friday
= 14000 + 6510
= $20510

Answer(s):$20510