Given:
The variance of a distribution = 195.
To find:
The standard deviation, rounded to the nearest thousandth.
Solution:
Standard deviation of a distribution is the square root of the variance of the distribution.
Here, the standard deviation of the distribution is
Therefore, the standard deviation is 13.964.
Answer:
The answer is below
Step-by-step explanation:
a) For a normal model the sample size has to be equal or greater than 30 so that it can be a normal distribution.
b) Given that:
μ = 11.2 minutes, σ = 4.8 minutes, n = 45
The z score determines how many standard deviations the raw score is above or below the mean. It is given by:
For x < 10 minutes
Therefore from the normal distribution table, P(x < 10) = P(z < -1.68) = 0.0465