The stadium tickets are priced at $12 and $7.  The number of $12-dollar tickets available is  1¹₅ that of the number of $7-dollar tickets. 2 out of 3 of the $12-dollar tickets and all the $7-dollar tickets were sold. The ticket sales amounted to $581. How much more would have been collected if all the tickets were sold?

	$12	$7
Comparing $12 and $7 tickets at first	6x1 = 6 u	5x1 = 5 u
Before	3x2 = 6 u
Change	- 2x2 = - 4 u	- 5 u
After	1x2 = 2 u	0 u

The number of 12 tickets at first is repeated.  Make the number of 12 tickets the same.  LCM of 3 and 6 is 6.

1¹₅ = ⁶₅

Number of $12 tickets : $7 tickets = 6 : 5

	$12	$7	Total
Number	4 u	5 u
Value	$12	$7
Total value	48 u	35 u	$581

Total amount collected from the sale of the sold tickets
= 48 u + 35 u
= 83 u

1 u = 581 ÷ 83 = 7

Number of $12-tickets left unsold
= 2 u 
= 2 x 7
= 14

More amount to be collected if all the tickets were sold
= 14 x 12
= $168

Answer(s): $168