SOLUTION: Mika bought a lamp at 90% of its book value. A week later she sold the lamp to her neighbor for over 25% of its book value and made a profit of $105 dollars. What is the book v

Algebra ->  Customizable Word Problem Solvers  -> Finance -> SOLUTION: Mika bought a lamp at 90% of its book value. A week later she sold the lamp to her neighbor for over 25% of its book value and made a profit of $105 dollars. What is the book v      Log On

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Question 772463: Mika bought a lamp at 90% of its book value. A week later she sold the lamp to her neighbor for over 25% of its book value and made a profit of $105 dollars.
What is the book value of the lamp.
How much did her neighbor pay?

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +b+ = the book value
She bought the lamp for +.9b+
She sold the lamp for +b+%2B+.25b+=+1.25b+
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The profit is:
( selling price ) - ( purchase price )
+105+=+1.25b+-+.9b+
+b%2A%28+1.25+-+.9+%29+=+105+
+b+=+105+%2F+.35+
+b+=+300+
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The neighbor paid +1.25b+
+1.25b+=+1.25%2A300+
+1.25b+=+375+
$375