Question 1137856
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C = P - 76


P + (P-76) = 200


2P = 200 + 76 = 276

P = 276/2 = 138     psychology books sold.  <U>ANSWER</U>


C = 200 - 138 = 62  chemistry book sold.    <U>ANSWER</U>


<U>CHECK</U>.   138 - 62 = 76.    ! Correct !
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Solved.