The tourist attraction tickets are priced at $21 and $12.  The number of $21-dollar tickets available is  2³₄ that of the number of $12-dollar tickets. 3 out of 7 of the $21-dollar tickets and all the $12-dollar tickets were sold. The ticket sales amounted to $8232. How much more would have been collected if all the tickets were sold?

	$21	$12
Comparing $21 and $12 tickets at first	11x7 = 77 u	4x7 = 28 u
Before	7x11 = 77 u
Change	- 3x11 = - 33 u	- 28 u
After	4x11 = 44 u	0 u

The number of 21 tickets at first is repeated.  Make the number of 21 tickets the same.  LCM of 7 and 11 is 77.

2³₄ = ¹¹₄

Number of $21 tickets : $12 tickets = 11 : 4

	$21	$12	Total
Number	33 u	28 u
Value	$21	$12
Total value	693 u	336 u	$8232

Total amount collected from the sale of the sold tickets
= 693 u + 336 u
= 1029 u

1 u = 8232 ÷ 1029 = 8

Number of $21-tickets left unsold
= 44 u 
= 44 x 8
= 352

More amount to be collected if all the tickets were sold
= 352 x 21
= $7392

Answer(s): $7392