Question

Profit and loss
A book was sold for Rs.550 with a profit of 10%. What is the cost price?​

Answer 1

SP=₹550

profit%=10%

let cp be 100 then sp will be 100+10=110

110/100×x=550

x=550×100/110=500

x=500

Answer 2

The cost price of the book is Rs. 500

Procedure:

Given:

Selling Price = $SP$ = Rs.550

Profit percent = $PP$ = 10%

To Find:

Cost Price, $CP$

Formulas Used:

$SP = CP + P$

Here, $SP$ is the selling price

         $CP$ is the cost price

         $P$ is the profit amount

Assumption:

Let us consider the cost price of the book to be Rs. $X$

Step-by-step explanation:

1. Assuming the cost price is Rs. $X$, we find the profit amount.
2. Profit amount is given by
   $P = \frac{PP}{100}*CP$
3. Substituting the values, we get the profit amount. So,
   $P=\frac{10}{100}*X=0.1X$
4. Now, using the value of profit amount, we need to calculate the value of $X$.
   $SP = CP+P$
5. Substituting the values here, we get
   $550 = X+0.1X$
6. Adding and simplifying the right-hand side, we get
   $550 = 1.1X$
7. On simplification, we get $X = 500$

Hence, the cost price of the book is Rs.500