SOLUTION: Mr. Ben bought some copies of book at GHC 5.00 each. 12 of the books got missing he then sold the rest at GHC 7.00 each and made a profit of GHC 150.00. How many books did he buys?

Algebra ->  Finance -> SOLUTION: Mr. Ben bought some copies of book at GHC 5.00 each. 12 of the books got missing he then sold the rest at GHC 7.00 each and made a profit of GHC 150.00. How many books did he buys?      Log On


   

Question 1187166: Mr. Ben bought some copies of book at GHC 5.00 each. 12 of the books got missing he then sold the rest at GHC 7.00 each and made a profit of GHC 150.00. How many books did he buys?
Answer by ikleyn(52835) About Me  (Show Source):
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Mr. Ben bought some copies of book at GHC 5.00 each.
12 of the books got missing he then sold the rest at GHC 7.00 each
and made a profit of GHC 150.00. How many books did he buys?
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Let n be the number of bought copies;  then the number of sold copies was (n-12).


The profit equation is


    7*(n-12) - 5n = 150.


Simplify and solve.


    7n - 84 - 5n = 150

        2n       = 150 + 84

        2n       = 234

         n       = 234/2 = 117.      ANSWER

Solved.