Question

For normally distributed data, what proportion of observations have a z-score less than 2.74.

Answer 1

Given: P(z<2.74), normal distribution

z-tables have z-scores listed and their corresponding probabilities. The probability is the area under the curve from 0 to the probability value. The proportion of observations have a z-score less than 2.74 from the z- tables is:

P(z<2.74) = 0.9969

This means 99.69% observations have a z-score less than 2.74.