C = 1.39 + 0.5(n - 1), where C is the cost and n is the number of days
C = 1.39 + 0.5(6)
C = $4.39
The trick to changing percent to decimal and decimal to present is simple
From percent to decimal : move the decimal place two places to the left and remove percent sign.
From decimal to percent: Move the decimal place two places to the right and put a percent sign.
Sooooo....
When you move the decimal - 79.2% - to the left two time - .792 - the answer left would be
A. 0.792
I believe the answer is 9.
Answer: 
This is the same as 
and it is also equivalent to 
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Explanation:
n is some placeholder for a number
one fourth of that number is 
which is the same as 
or 
since 1/4 = 0.25
From here, we subtract off 2 to get as one possible final answer.
