# The average time a subscriber spends reading the local newspaper is 49 minutes. For the 10% who spend the most time reading the paper, how much time do they spend?

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Assume the standard deviation is 16 minutes and that the times are normally distributed

Assume the standard deviation is 16 minutes and that the times are normally distributed

##### 1 Answer

Aug 19, 2016

#### Explanation:

basically we are asked to find the 90th percentile which can be found as such

1) look up the .90 p-value from a z table and get the z score

2) use the formula to compute z score but now solve from x

this means that the top 10% read more than