Problem Solving (PS) | Re: A Certain radio costs the merchant $72. At what price must the merchan

Let, S.P. be= x
Now, According to question,
C.P. + Profit = S.P
=> C.P. + 20% of S.P. = S.P.
=> 72 + 20x/100 = x
=> x - 20x/100 = 72
=> 80x/100 = 72
=> x = 72 * 100x/80
=> x = 90
Hence, Answer choice(c)

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