$3/6 = .50 per orange
$2.40/3 = .80 per grapefruit
10(.50) + 11(.80) =
$5.00 + $8.80 = $13.80
Answer:

Step-by-step explanation:
Multiply both sides by 7 to get rid of the denominator on the Right Side (RS). Do the same for the left side (LS) by multiplying both sides by 5 to get:

Simplify: 
Divide both sides of the equation by 7 to get: 
I hope it's clear enough.