Question

By selling a book for \[Rs.10\] , the publisher loses \[\dfrac{1}{{11}}\] of what it costs him. His cost price is ....
A.\[Rs.9\]
B.\[Rs.10\]
C.\[Rs.11\]
D.\[Rs.12\]

Answer 1

Hint: The Indian rupee is the country's official currency. While the rupee is divided into \[100\] paise, \[1\] rupee coins are the smallest denomination in use as of \[2019\] . The currency's issuance is overseen by the Reserve Bank of India.

Complete step by step solution:
A trade in which a product or service is exchanged for money is known as selling. It may also refer to the method of persuading someone or a company to purchase something. Here in the question, we are dealing with the sales of a book.
Let's assume that the cost price is \[x\] .
It is given that the selling price of the book, selling price \[ = Rs.10\]
Therefore, \[loss = x \times \dfrac{1}{{11}}\]
\[ \Rightarrow loss = \dfrac{x}{{11}}\]
We have to find out the cost price.
So, Cost price \[ = \] selling price \[ + \] loss
After substituting the values, we will get,
\[x = 10 + \dfrac{x}{{11}}\]
We are rearranging the formula to calculate the value of \[x\] .
That is, \[x - \dfrac{x}{{11}} = 10\]
Now, we are performing the subtraction of the fractions on the left side.
\[ \Rightarrow \dfrac{{11x - x}}{{11}} = 10\]
\[ \Rightarrow \dfrac{{10x}}{{11}} = 10\]
\[ \Rightarrow x = 11\]
Hence, the publisher’s cost price is \[Rs.11\] .
So, the answer is Option C.
So, the correct answer is “Option C”.

Note: According to the question, we are using the formula, Cost price \[ = \] selling price \[ + \] loss. When doing calculations, do it carefully without any errors.