A shirt was sold for $40, incurring a loss of 20%. Find the cost price.

Correct option is A

Given:
Selling Price (SP) = $40
Loss = 20%
Formula Used:
​$$\text{SP} = \text{CP} \times \left(1 - \frac{\text{Loss\%}}{100}\right) \\$$​​
Solution:
​$$40 = \text{CP} \times \left(1 - \frac{20}{100}\right) \\40 = \text{CP} \times \frac{80}{100} \\40 = \text{CP} \times 0.8 \\\text{CP} = \frac{40}{0.8} = 50 \\$$​​
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