Question

Doug and his friends had dinner at the Burger Barn. The meal cost $80.00. They left the waitress a tip of 10%. How much did the friends pay for dinner altogether?

Answer 1

80.00 * 1.10 = 88.00

Answer 2

Surely you know how to take 10% of something !

take 10% of 80, add it to 80, or

in one step: What is 1.1*80 ?