Answer:
t = 3.46 hours, or 3 hours 28 minutes
Step-by-step explanation:
78 dozen donuts in 2 hours immediately reduces to 39 dozen/hour.
Donuts produced as a function of time: D(t), where t is the number of hours the macine runs.
Set D(t) = 135 dozen = (39 dozen/hr)t.
Solving this equation for t, we get:
t = 135/39 hours, or t = 3.46 hours, or 3 hours 28 minutes
