Percent of a number: tax, discount, and more

Erika ate brunch at a restaurant. The bill came to $12,20. If she left a 15% tip, how much was the tip?

Write the percentage as a decimal.

15% = 0.15

Multiply the decimal by the amount of the bill. Multiply as you would multiply whole numbers, then write the decimal point in the answer.

The tip was $1.83.

Your parents took your family out to dinner. Your parents wanted to give the waiter a 15% tip. If the total amount of the dinner was $40.00, what should be paid to the waiter as a tip?

The tip should be: $