A person sold a watch for $450, incurring a loss of 10%. Find the cost price.

Correct option is C

Given:
Selling Price (SP) = $450
Loss Percentage = 10%
Formula Used:
$$\text {Selling Price} = \text{CP}(1 - \frac{Loss \%}{100})$$​​
Solution:
​$$CP = \frac{450}{1 - \frac{10}{100}} \\ CP = \frac{450}{1 - 0.1} \\ CP = \frac{450}{0.9} \\CP = 500 \\$$​​
Therefore, the cost price of the watch is $500.