# Sampling Distribution of sampling mean

**Question description**

Borachio eats at the same fast food restaurant every day. Suppose the time *X* between the moment Borachio enters the restaurant and the moment he is served his food is normally distributed with mean 4.2 minutes and standard deviation 1.3 minutes.

- Find the probability that when he enters the restaurant today it will be at least 5 minutes until he is served.
- Find the probability that average time until he is served in eight randomly selected visits to the restaurant will be at least 5 minutes.

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