At a concert hall, each adult ticket cost $25 and each child ticket cost $13. On Thursday, the number of adult tickets sold was 145 less than the number of child tickets. On Friday, the number of adult tickets sold decreased by 20% while the number of child tickets sold increased by 40%. If a total of 1523 tickets were sold on Friday, how much money was collected on Thursday?

	Adult tickets	Child tickets	Total tickets
Before	1 u	1 u + 145	2 u + 145
Change	- 0.2 u	+ 0.4 u + 58
After	0.8 u	1.4 u + 203	2.2 u + 203

20% x 1 u = ²⁰₁₀₀ x 1 u = 0.2 u 
40% x 1 u = ⁴⁰₁₀₀ x 1 u = 0.4 u
40% x 145 = ⁴⁰₁₀₀ x 145 = 58

Number of tickets sold on Friday
= 0.8 u + 1.4 u + 203
= 2.2 u + 203

2.2 u + 203 = 1523
2.2 u = 1523 - 203
2.2 u = 1320

1 u = 1320 ÷ 2.2 = 600

Amount collected from adult tickets on Thursday
= 1 u x 25
= 600 x 25
= $15000

Amount collected from child tickets on Thursday
= 13(1 u + 145)
= 13(600 + 145)
= 13 x 745
= $9685

Total amount collected on Thursday
= 15000 + 9685
= $24685

Answer(s):$24685