The bird park tickets are priced at $16 and $6.  The number of $16-dollar tickets available is  1⁵₆ that of the number of $6-dollar tickets. 2 out of 5 of the $16-dollar tickets and all the $6-dollar tickets were sold. The ticket sales amounted to $3724. How much more would have been collected if all the tickets were sold?

	$16	$6
Comparing $16 and $6 tickets at first	11x5 = 55 u	6x5 = 30 u
Before	5x11 = 55 u
Change	- 2x11 = - 22 u	- 30 u
After	3x11 = 33 u	0 u

The number of 16 tickets at first is repeated.  Make the number of 16 tickets the same.  LCM of 5 and 11 is 55.

1⁵₆ = ¹¹₆

Number of $16 tickets : $6 tickets = 11 : 6

	$16	$6	Total
Number	22 u	30 u
Value	$16	$6
Total value	352 u	180 u	$3724

Total amount collected from the sale of the sold tickets
= 352 u + 180 u
= 532 u

1 u = 3724 ÷ 532 = 7

Number of $16-tickets left unsold
= 33 u 
= 33 x 7
= 231

More amount to be collected if all the tickets were sold
= 231 x 16
= $3696

Answer(s): $3696