The initiate is: "Movie trailers are designed to entice audiences by showing scenes from coming attractions. Several trailers are usually shown in a theatre before the start of the main feature, and most are available via the Internet. The duration of a movie trailer is approximately Normal, with mean 150 seconds and standard deviation 30 seconds."

The two question are: Ten percent of movie trailers have durations above what value?

and In a sample of 16 randomly selected movie trailers, find the probability that the sample mean duration is greater than 4 minutes and 30 seconds?

I was thinking using first the Z-score of 10% above mean and for the second I'm pretty lost. What do you think about the response