Question

Suppose a normal distribution has a mean of 266 and a standard deviation of

12. What is P(x > 278)?

O A. 0.16

O B. 0.475

O c. 0.84

O D. 0.975

Answer 1

A. 0.16

Explanation:

I just took the test

Answer 2

P(x>278) is 0.16

Explanation:

We are given that a normal distribution has a mean of 266 and a standard deviation of 12.

Mean =
`\mu =266`

Standard deviation =
`\sigma = 12`

We are supposed to find P(x > 278)

So, Formula :
`Z=(x-\mu)/(\sigma)`

`Z=(278-266)/(12)`

Z=1

Refer the z table for p value

p value = 0.8413

P(x<278) is 0.84

P(x>278)=1-P(x<278)=1-0.84=0.16

Option A is true

Hence P(x>278) is 0.16