On Thursday, 280 more women than men attended a concert. On Friday, the number of women decreased by 10% and the number of men increased by 80%. 657 audience attended the concert on Friday. If each ticket cost $12, how much money was collected from the sale of concert tickets on Thursday?

	Women		Men
Comparing between the women and the men at first	280 more
Before	10x1	+ 280	5x2
Change	- 1x1	- 28	+ 4x2
After	9x1	+ 252	9x2

	Women		Men
Before	10 u + 280		10 u
Change	- 1 u - 28		+ 8 u
After	9 u + 252		18 u

10% = ¹⁰₁₀₀ = ¹₁₀

80% = ⁸⁰₁₀₀ = ⁴₅

10% x 280
= ¹⁰₁₀₀ x 280
= 28

280 - 28 = 252

Total number of tickets sold on Friday 
= 9 u + 252 + 18 u
= 27 u + 252 

27 u + 252 = 657
27 u = 657 - 252
27 u = 405

1 u = 405 ÷ 27 = 15

Total number of tickets sold on Thursday
= 10 u + 280 + 10 u 
= 20 u + 280
= 20 x 15 + 252
= 552

Amount collected from the sale of concert tickets on Thursday
= 552 x 12
= $6624

Answer(s): $6624