The zoo tickets are priced at $11 and $9.  The number of $11-dollar tickets available is  2²₅ that of the number of $9-dollar tickets. 3 out of 4 of the $11-dollar tickets and all the $9-dollar tickets were sold. The ticket sales amounted to $432. How much more would have been collected if all the tickets were sold?

	$11	$9
Comparing $11 and $9 tickets at first	12x1 = 12 u	5x1 = 5 u
Before	4x3 = 12 u
Change	- 3x3 = - 9 u	- 5 u
After	1x3 = 3 u	0 u

The number of 11 tickets at first is repeated.  Make the number of 11 tickets the same.  LCM of 4 and 12 is 12.

2²₅ = ¹²₅

Number of $11 tickets : $9 tickets = 12 : 5

	$11	$9	Total
Number	9 u	5 u
Value	$11	$9
Total value	99 u	45 u	$432

Total amount collected from the sale of the sold tickets
= 99 u + 45 u
= 144 u

1 u = 432 ÷ 144 = 3

Number of $11-tickets left unsold
= 3 u 
= 3 x 3
= 9

More amount to be collected if all the tickets were sold
= 9 x 11
= $99

Answer(s): $99