Question

At the spring fling, john can make 5 cups of hot tea in 2 minutes. Sammy can make 6 cups of hot tea in 2.5 minutes. How long should it take them to make hot tea for all 245

Answer 1

john's rate = 5 cups/2 min = 2.5 cups/min
sam's rate = 6 cups/2.5 min = 2.4 cups/min
combined rate = 4.9 cups/min
so time to make 245 cups = 245/4.9 = 50 minutes

check:
in 50 minutes, john can make 50(5/2) = 125 cups
in 50 minutes , sam can make 50(6/2.5) = 120 cups
total = 245 cups