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Multi-step problems with percents

Peter took one of his friends out to lunch. The lunches cost $100 and he paid 12% sales tax. If Peter left an 18% tip on the$100, how much in total did he pay?

First find the tax. Write 12% as the decimal 0.12 before using it in the equation.

 tax = tax percentage × amount = 0.12 × 100 = 12

The tax was $12. Now find the tip. Write 18% as the decimal 0.18 before using it in the equation.  tip = tip percentage × amount = 0.18 × 100 = 18 The tip was$18.

Finally, find the total cost.

 total cost = cost + tax + tip = 100 + 12 + 18 = 130

The total cost was $130. In August, Music Maze priced all the compact discs (CDs) at$16. In October, these same CDs were discounted 25%, and in December they were reduced an additional 8%. What was the price of one CD after both discounts?

Round the answer to the nearest hundredth

The final cost is \$