80% of the arrivals to a COVID19 vaccination center pre-register themselves on the COWIN portal before arriving whereas the rest walk in and register at the venue. Pre-registered individuals verify their registration upon arrival and then proceed to one of the vaccinators. Walk-ins visit the registration desk and then proceed to one of the vaccinators. Verification step (including waiting) takes 5 minutes whereas registration step (including waiting) takes 15 minutes. Vaccination (including counselling) takes 5 minutes and is preceded by an additional waiting time of 10 minutes. Individuals spend 10 minutes after vaccination (instead of the recommended 30 minutes) to allow observation of adverse reactions to the vaccine. On average, there are 240 individuals in the vaccination camp excluding staff (all staff at the vaccination camp are vaccinated).

A large domestic airport handles 90 take-offs per hour. For take-off, an aircraft leaves the gate, taxies for some distance and awaits its turn on the runway. Average time spent by an aircraft between leaving the gate and taking off is 4 minutes. Similarly, aircrafts spend average of 8 minutes between landing and reaching their gate. What is the average number of aircrafts on the runway at the airport?

In the above example, flights spend 1.5 hours at the gate between one arrival and the next departure. If the airport has 300 gates, what fraction of gates are occupied on average?

Grab-a-Bite, a food delivery business, targets an average delivery time of 30 minutes for each order and delivers 100 orders/hr on average. Each delivery partner is assigned to the order as soon as it is received and stays with it until it is delivered. If a partner spends 4 hours on the Grab-a-Bite platform, what is the rate at which delivery partners log into the platform?