A dollar store has six checkout lanes. The clerks in each lane have the same$$ abilities, with each clerk being able to checkout a customer in $4$ minutes on average. At its busiest$$ times, customers to the dollar store arrive at the checkout counters at the rate of $53$ per hour.$$

LOADING... Click the icon to view the Upper L Subscript q values for the queuing model.

Part $2$

a$.$ The average waiting time if all $6$ checkout lanes are being used is

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$0\mathrm{.}2678$ minutes. $($Enter your response rounded to four decimal$$ places.$)$

Part $3$

b$.$ The dollar store is contemplating closing one of the checkout lanes. If they reduce the number of lanes from $6$ to $5$ then how will customer wait time be affected during the busiest store$$ hours?

The average waiting time when there are $5$ checkout lanes will increase by

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