# Normal Probabilities - Calculating using Z Score

If a drive to work each morning is Âµ = 38 mins with a Ïƒ = 5 mins, on a randomly selected morning what is the probability that the drive will take between 36 and 40 mins?

IQ scores form a normal distribution with Âµ = 100 and Ïƒ = 15. Individuals with IQs above 140 are classified in the genius category. What proportion of the population consists of geniuses? Individuals between 90 and 110 are classified as average. What is the proportion of the population that is classified as average?

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If a drive to work each morning is Âµ= 38 mins with a Ïƒ= 5 mins. On a randomly selected morning what is the probability that the drive will take between 36 and 40 mins?

Let X be the time taken to drive to work. Let assume that X is normal with mean Âµ = 38 and standard deviation Ïƒ = ...

#### Solution Summary

The solution provides a step by step method for the calculation of probability using the Z score and normal distributions. The solutions are accompanied by graphs.