Exercise $7\mathrm{.}5$ A restaurant receives on average $1,200$ customers per day $($between

$10$ a$.$m$.$ and $10$ p$.$m$.).$ During peak times $(12$ p$.$m$.$ to $3$ p$.$m$.$ and $6$ p$.$m$.$ to $9$ p$.$m$.),$ the

restaurant receives around $900$ customers in total and, on average, $90$ customers can

be found in the restaurant at a given point in time. At non$-$peak times, the restaurant

receives $300$ customers in total and, on average, $30$ customers can be found in the

restaurant at a given point in time.

What is the average time that a customer spends in the restaurant during peak

times?

What is the average time that a customer spends in the restaurant during non$-$peak

times?

The restaurant's premises have a maximum capacity of $110$ customers. This

maximum capacity is sometimes reached during peak times. The restaurant

manager expects that the number of customers during peak times will increase

slightly in the coming months. What can the restaurant do to address this issue

without investing in extending its building?