Question

Sam is shopping for clothes. There's a 9% sales tax where he lives. Select the expression that gives the price of clothes after including the sales tax, where c is the original cost of the clothes.

1c + 0.9c

Incorrect Response
1.09c + 0.09c

Correct Answer
1.09c

Answer 1

1.09c

Explanation:

The clothes cost c before tax.

The tax is 9% of the price of the clothes, or 9% of c.

To find a percent of a number, change the percent to a decimal and multiply by the number.

9% as a decimal is 0.09

9% of c = 9% * c = 0.09c

The amount of tax is 0.09c.

Now we add the amount of tax to the original price, c.

c + 0.09c = 1.09c

Answer: 1.09c