116k views
1 vote
A given data value has a Z-value equal to 1.2. Assuming a normal (i.e., symmetrical) continuous probability distribution, how many standard deviations is the data value from the mean?

User Blue
by
5.0k points

2 Answers

5 votes

Answer:

1.2

Explanation:

the number of standard deviations that the data value is away from the mean is 1.2 standard deviations, and thats because the units of the Z values are standard deviations.

if you remember the Z value formula is (X - mean) / SD, you are subtracting the X (data value) from the mean, and then dividing by standard deviations to get the number of standard deviations that the data value is away from the mean

if the Z value is positive that means that the data value is above from the mean.

if the Z value is negative that means that the data value is below from the mean

User Hamed Naeemaei
by
5.5k points
6 votes

Answer: 1.2

Explanation:

Let x be a random data value that follows a normal distribution.

The formula to find the z-value :-


z=(x-\mu)/(\sigma), where
\mu is the population mean and
\sigma is the standard deviation.

Given : A data value has a Z-value equal to 1.2.

Then, we have


z=(x-\mu)/(\sigma)\\\\\Rightarrow\ 1.2=(x-\mu)/(\sigma)\\\\\Rightarrow\ x-\mu=1.2\sigma\\\\\Rightarrow\ x=\mu+1.2\sigma

Hence, the data value is 1.2 standard deviations from the mean.

User Dmnc
by
4.8k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.