Part (a)
Answer: $32.50
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Work Shown:
Each ticket costs $16. If you buy four of them, then you paid 4*16 = 64 dollars.
The total bill was $96.50
This leaves 96.50-64 = 32.50 for parking.
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Part (b)
Answer: y = 16x+32.50
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Work Shown:
x = number of tickets
y = total bill (in dollars)
1 ticket costs 16 dollars
x tickets cost 16x dollars since we multiply both values by x
Add on the cost of parking to get a total bill of y = 16x+32.50
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Part (c)
Answer: at most 13 tickets
In other words, 13 is the max you can get.
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Work Shown:
Plug y = 250 into the equation found back in part (b). Solve for x
We'll follow PEMDAS in reverse to isolate x
y = 16x+32.50
250 = 16x+32.50
16x+32.50 = 250
16x = 250-32.50
16x = 217.5
x = 217.5/16
x = 13.59375
Since we can't buy a fraction of a ticket, we must round down to the nearest whole number. We cannot round to x = 14 despite the value 13.59375 being closer to 14 as it is to 13.
x = 13 is the answer we're after.
If we plug in x = 13, we get
y = 16x+32.50 = 16*13+32.50 = 240.5
while x = 14 leads to
y = 16x+32.50 = 16*14+32.50 = 256.5
The first result of $240.50 is under $250 while the second result $256.50 is over $250. So that's why x = 13 is the largest number of tickets we can buy.
