Mackenzie spent $20 at the local farmer’s market. She bought b pounds of blueberries that cost $4 per pound, and r pounds of raspberries that cost $6 per pound. She wrote the equation 4 b + 6 r = 20 to represent the cost of all the fruit. Which is equivalent to Mackenzie’s equation?
b = 5 minus three-halves r
b = 80 minus 240 r
r = StartFraction 10 Over 3 EndFraction + two-thirds b
r = 120 + 240 b