Question 290209
The amount of water in the container can be modeled by this equation
{{{WaterInContainer = 50 + (AmountAddedPerMinute - AmountPumpedOutPerMinute) * minutes}}}  or
{{{w = 50 + (4 - 5) m}}}
{{{w = 50 - m}}} 
so when will the container be empty? It is empty when w = 0

{{{0 = 50 - m}}}
{{{-50 = -m}}}
{{{50 = m}}} 
50 minutes and the container is dry