Given that x is a normally distributed random variable with a mean of 28 and a standard deviation of 7, find the following probability:

P(x

Question

Given that x is a normally distributed random variable with a mean of 28 and a standard deviation of 7, find the following probability: 

P(x < 28)

kropot72 · Answer

Can you find the z-score needed to solve this?

anonymous · Answer

I forgot how I keep missing up

kropot72 · Answer

$$z=\frac{(x-\mu)}{\sigma}$$
Just put in the values$$x=28$$
$$\mu=28$$$$\sigma=7$$

anonymous · Answer

I have this z=x-μ/o

P(X<28)
Z=(4-28)/7=2.86
Probability is .9979

z=x-μ/o

(28-28)/7=0 but my teacher said it's half right and said to  find the area a to the left of this z-score.

kropot72 · Answer

The correct z-score is your calculation (28 - 28)/7 = 0. When you look up the standard normal distribution table what probability do you get for z = 0.0 ?

anonymous · Answer

0.5000

kropot72 · Answer

Good work! P(x < 28) = 0.500

anonymous · Answer

great thanks !!!