The museum tickets are priced at $18 and $11.  The number of $18-dollar tickets available is  2¹₅ that of the number of $11-dollar tickets. 2 out of 5 of the $18-dollar tickets and all the $11-dollar tickets were sold. The ticket sales amounted to $4026. How much more would have been collected if all the tickets were sold?

	$18	$11
Comparing $18 and $11 tickets at first	11x5 = 55 u	5x5 = 25 u
Before	5x11 = 55 u
Change	- 2x11 = - 22 u	- 25 u
After	3x11 = 33 u	0 u

The number of 18 tickets at first is repeated.  Make the number of 18 tickets the same.  LCM of 5 and 11 is 55.

2¹₅ = ¹¹₅

Number of $18 tickets : $11 tickets = 11 : 5

	$18	$11	Total
Number	22 u	25 u
Value	$18	$11
Total value	396 u	275 u	$4026

Total amount collected from the sale of the sold tickets
= 396 u + 275 u
= 671 u

1 u = 4026 ÷ 671 = 6

Number of $18-tickets left unsold
= 33 u 
= 33 x 6
= 198

More amount to be collected if all the tickets were sold
= 198 x 18
= $3564

Answer(s): $3564