Explanation
To find the cost of the doll when it is sold for Rs. 220 with a profit rate of 10%, we can use the following formula:
Selling Price=Cost Price+Profit
Given that the profit is 10% of the cost price, we can express the profit as:
Profit=0.10×Cost Price
Let the cost price be C. Therefore, the selling price can be expressed as:
Selling Price=C+0.10C=1.10C
We know the selling price is Rs. 220, so we can set up the equation:
1.10C=220
Now, we can solve for C:
C=2201.10=200
Thus, the cost of the doll was Rs. 200.