A trader lost 10% by selling a shirt for ₹850. He will gain x%' by selling it for ₹1530, the value of x is:

Correct option is D

Given:
A trader lost 10% by selling a shirt for ₹850.
He will gain x% by selling it for ₹1530.

Formula Used:
Profit = Selling Price - Cost Price 

​$$\text{Profit \%} = \left( \frac{\text{SP} - \text{CP}}{\text{CP}} \right) \times 100$$​​
Solution:

Let the cost price of the shirt be C .

When the trader sells the shirt for ₹850, he incurs a loss of 10%. The relationship between selling price and cost price is:

$$\text{Selling Price} = C - 10\% \text{ of } C = 0.90C.$$​​
So,
850 = 0.90C.
C $$= \frac{850}{0.90} = \frac{8500}{9} \approx 944.44.$$​
Now, if the trader sells the shirt for ₹ 1530, the selling price is ₹ 1530. The profit is:
$$\text{Profit} = \text{Selling Price} - C = 1530 - 944.44 = 585.56.$$​​
$$x\% = \left( \frac{585.56}{944.44} \right) \times 100 \approx 62\%.$$​