If a shopkeeper sells an item for $90 at a loss of 10%, what was the cost price?

If a shopkeeper sells an item for $90 at a loss of 10%, what was the cost price?

Step 1: Understand that the selling price is $90 and the shopkeeper sold it at a loss of 10%.
Step 2: Let the cost price be represented by 'x'.
Step 3: Since there is a loss of 10%, the selling price is 90% of the cost price. This can be written as: Selling Price = Cost Price - Loss.
Step 4: The loss can be calculated as 10% of the cost price, which is 0.10 * x.
Step 5: Therefore, the selling price can also be expressed as: Selling Price = x - (0.10 * x) = 0.90x.
Step 6: We know the selling price is $90, so we can set up the equation: 0.90x = $90.
Step 7: To find the cost price 'x', divide both sides of the equation by 0.90: x = $90 / 0.90.
Step 8: Calculate the value: x = $100.
Step 9: Therefore, the cost price of the item is $100.

Cost Price and Selling Price – Understanding the relationship between cost price, selling price, and loss percentage.
Percentage Calculations – Calculating losses and profits as percentages of the cost price.