Two friends, Alejandra and Mia, agreed to split the check at a restaurant. Alejandra ordered $12 worth of food and Mia ordered $18 worth. At the end of the meal, Alejandra put her $12 contribution on the table with a 20% tip added, and Mia put her $18 contribution on the table with a 15% tip added.

The total tip left by Alejandra and Mia is equal to r% of the total check for their table, where the "total check" amount does not include the tip. What is r?

Question

Two friends, Alejandra and Mia, agreed to split the check at a restaurant. Alejandra ordered $12 worth of food and Mia ordered $18 worth. At the end of the meal, Alejandra put her $12 contribution on the table with a 20% tip added, and Mia put her $18 contribution on the table with a 15% tip added. 

The total tip left by Alejandra and Mia is equal to r% of the total check for their table, where the "total check" amount does not include the tip. What is r?

anonymous · Answer

12 X .20 = 2.4 
18 X .15 = 2.7 
r= 5.1