# Normal Probabilities - Using Z Score

A normal distribution has a mean of u= 40 and o=10. if a vertical line is drawn through the distribution at x= 55, what proportion of the scores on the right side of the line?

A normal distribution has a u= 80 and o= 10. what is the probability of randomly selecting a score greater than 90 from this distribution?

A normal distribution has a mean of u= 100 and o= 20. if one score is randomly selected from the probability that the score will be less than x= 84?

© BrainMass Inc. brainmass.com October 10, 2019, 7:30 am ad1c9bdddfhttps://brainmass.com/statistics/data-collection/normal-probabilities-z-score-584159

#### Solution Preview

A normal distribution has a mean of u= 40 and o=10. If a vertical line is drawn through the distribution at x= 55, what proportion of the scores on the right side of the line?

Answer

We need P (X > 55)

P (X > 55) = = P (Z > 1.5) ...

#### Solution Summary

The solution provides step by step method for the calculation of probability using the Z score. The normally distribution has mean of u=100 and o=20. The expert determines if the probability of randomly selecting a score is greater than 90 from the distribution. The expert also determines if one score is randomly selected from the probability that the score will be less than x=84.