SOLUTION: A farmer bought a number of pigs for $200. However, 4 of them died before he could sell the rest at a profit of 7 per pig. His total profit was $72. How many pigs did he originally

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Question 1139187: A farmer bought a number of pigs for $200. However, 4 of them died before he could sell the rest at a profit of 7 per pig. His total profit was $72. How many pigs did he originally buy?
Found 2 solutions by ikleyn, greenestamps:
Answer by ikleyn(52787)   (Show Source): You can put this solution on YOUR website!
.
Let n = # of pigs originally bought.


Then you have this equation from the condition


     -  = 7,   or


     -  = 7.


Multiply both sides by n*(n-4), simplify and solve for n


    272n - 200*(n-4) = 7n*(n-4)

    72n + 800 = 7n^2 - 28n

    7n^2 - 100n - 800 = 0

    n =  = .


The solution to the problem is the positive integer  n =  =  = 20.


ANSWER.  There were 20 pigs originally.


CHECK.     -  = 17 - 10 = 7  dollars  profit for each of 16 sold pigs.   ! Correct !

Solved.

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Answer by greenestamps(13200)   (Show Source): You can put this solution on YOUR website!

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