Q20 of 83 Page 90

While selling a pen for Rs. 24 the loss in percentage is equal to its cost price. Find the cost price of pen. The cost price of pen is less than 50.

Let C.P of pen be x

⇒ Loss = x%


If C.P = Rs.100, then loss = Rs. X


And, if C.P = x, then



Also, Loss = C.P – S.P



⇒ x2 – 100x + 2400 = 0


⇒ x2 – (60 + 40)x + 2400 = 0


⇒ x2 – 60x – 40x + 2400 = 0


⇒ x – 60 = 0 or x – 40 = 0


⇒ x = 60 or x = 40


But given C.P is less than 50


⇒ Cost Price(C.P) = Rs.40


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