Question

A set of data has a normal distribution with a mean of 5.1 and a standard deviation of 0.9. Find the percent of data greater than 6.9.
about 16 %

about 34%

about 13.5%

about 2.5%

Answer 1

P(x > 6.9) = 1 - P(x < 6.9) = 1 - P[z < (6.9 - 5.1)/0.9] = 1 - P(z < 2) = 1 - 0.97725 = 0.02275.

Therefore P(x > 6) is about 2.5%