Question 1111601
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<pre>
Cost 5 years ago = {{{P*(1+0.05)^(-5)}}}    where P is the current price.


                 = {{{3.89/(1+0.05)^5}}} = 3.05 dollars per gallon.
</pre>

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<U>Be aware</U>:  &nbsp;The answers AND the formulas of BOTH other tutors regarding the milk price per gallon 5 years ago are &nbsp;&nbsp;<U>W R O N G</U>.



&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;My apologies for their illiteracy in such simple issue.