Question

A distribution of values is normal with a mean of 188 and a standard deviation of 20.8. Find the probability that a randomly selected value is less than 167.2.

Answer 1

Answer:0.8413

Step-by-step explanation:

Mean= 188, Std Dev. =20.8, Z=(x-mean)/Std Dev

P(X less than 167.2)= P(Z less than (167.2-188)/20.8)

=P(Z less than (-20.8/20.8))

=P(z less than -1)= P(Z less 1)

The value of 1 in the normal distribution table is 0.3413

So we add 0.5 to 0.3413 =0.8413