Question

In a sample with a mean of 46 and a standard deviation of 8, what is the probability of randomly selecting a score below 64?

a) 0.7881
b) 0.8119
c) 0.8681
d) 0.8919

Answer 1

To find the probability of randomly selecting a score below 64, we need to calculate the z-score using the standard normal distribution.

Step-by-step explanation:

To find the probability of randomly selecting a score below 64, we need to use the standard normal distribution and calculate the z-score.

Z = (X - μ) / σ

Where X is the given score, μ is the mean, and σ is the standard deviation.

Z = (64 - 46) / 8 = 2.25

Using a standard normal distribution table or a calculator, we can find that the probability of a z-score of 2.25 or less is approximately 0.9875.

Therefore, the probability of randomly selecting a score below 64 is approximately 0.9875.