Answer: Each ticket costs $32
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Step-by-step explanation:
Let x be the cost of one ticket. If four people buy a ticket each, then they collectively spend a total of 4x dollars for those tickets. Add on 4*3 = 12 dollars from the fact that they bought the ice cream, and we arrive at the expression 4x+12. This is the total amount spent in dollars for the tickets and ice cream combined.
Set this expression equal to 140 and solve for x
4x+12 = 140
4x = 140-12
4x = 128
x = 128/4
x = 32
This says that each ticket costs $32
If one ticket costs $32, then four of them cost a total of 4*32 = 128 dollars. Add on the $12 spent on the ice cream to get 128+12 = 140, which helps verify we have the correct ticket price.
Another way to verify is to replace x with 32 in the original equation we set up, then simplify like so
4x+12 = 140
4*32+12 = 140
128+12 = 140
140 = 140
This is very similar to the previous verification technique used earlier.