Answer
$3.\overline3\ hr$
Work Step by Step
Find the total number of drops.
$1000\ mL\times\frac{10\ drops}{1\ mL}=10000\ drops$
Divide the number of drops by the flow rate to find the time.
$10000\ drops\div\frac{50/ drops}{1\ min}=10000\ drops\times\frac{1\ min}{50\ drops}=200\ min$
Convert to hours.
$200\ min=200\ min\times\frac{1\ hr}{60\ min}=3.\overline3\ hr$
