On the average 10 customers arrive each half-an-hour at the

Question

On the average 10 customers arrive each half-an-hour at the checkout counter at a local pharmacy store.

1. What is the probability that more than 10 customers will arrive at the checkout counter in 27 min.?
2. What is the probability that less than 7 customers arrive at the checkout counter in 24 min.?
3. What is the probability that no more than 6 customers arrive at the checkout counter in 18 min.?
4. What is the probability that no less than 4 customers arrive at the checkout counter in 22.5 min.?
5. What is the probability that at least 2 but less than 5 customers arrive at the checkout counter in 30 min.?