Question

The list price of a parker pen is RS. 160 and a customer buys it for Rs. 122.40 after two successive discounts. If first is 10% then the second is:
(a). 18%
(b). 17%
(c). 16%
(d). 15%

Answer 1

Hint: Here, we may first find the price of the pen after a discount of 10% and then we will apply the second discount on that price. The sum of both of these discounts must be equal to the difference between the list price and selling price.

Complete step-by-step answer:
Since, it is given that the list price of the parker pen is = Rs. 160
The price at which the customer buys it is = Rs. 122.40
So, the total discount on the pen given to the customer is = Rs. 160 – Rs. 122.40 = Rs. 37.60
Since, the value of first discount is = 10%
So, the value of 10% of Rs. 160 is =$\dfrac{10}{100}\times 160$= Rs. 16
So, the value of first discount given to the customer is = Rs. 16
Therefore, after applying this discount that is after subtracting Rs. 16 from the initial price of the pen, the new price of the pen is:
Rs.160 – Rs. 16 = Rs. 144
Now, let the 2nd discount applied on the pen be = x%
So, the x% of Rs. 144 is =$\dfrac{x}{100}\times 144=1.44x$
Since, the total discount on the pen is = Rs. 37.60
Therefore,
Rs. 16 + Rs. 1.44x = Rs. 37.60
$\begin{align}
  & 1.44x=37.60-16 \\
 & x=\dfrac{21.60}{1.44} \\
 & x=15 \\
\end{align}$
So, the value of x is 15 and therefore, the second discount is 15%.
Hence, option (d) is the correct answer.

Note: Students should note here that the second discount should be applied on the reduced price obtained after applying the discount of 10% on the actual price of the pen.