Standard Deviation and Normal Distribution

According to the normal distribution, what percentage of data falls within 1 standard deviation?

• 25%

• 68%

• 95%

• 99.7%

According to the normal distribution, how much of the data falls within 3 standard deviations?

• 25%

• 68%

• 95%

• 99.7%

What is the standard deviation of this distribution? (how far is it from the mean to the first stdev line?)

• 1010

• 20

• 60

• 40

This data is normally distributed.  What percent of the data is in the shaded region?

• 68%

• 95%

• 99.7%

• 50%

In a normal distribution, what percent of the values lie within one standard deviation of the mean?

(from z = -1 to z = 1)

• 13.5%

• 34%

• 95%

• 68%

Question 11

• 1

• 2

• 3

• 4

​ The monthly income of 5000 workers at the Microsoft plant are distributed normally. Suppose the mean monthly income is $1250 and the standard deviation is $250.

Creating a normal distribution curve shows that the percentage of workers who earn between $750 and $1500 per month is ​ (a)  

• 800 workers

• 125 workers

• 81.5% of workers

• 97.5% of workers

In any normal distribution, about what percent of values are within 1 standard deviation of the mean?

• 50%

• 68%

• 95%

• 99.7%

​ The monthly income of 5000 workers at the Microsoft plant are distributed normally. Suppose the mean monthly income is $1250 and the standard deviation is $250.

Creating a normal distribution curve shows that the percentage of workers who earn less than $1750 per month is ​ (a)  

• 800 workers

• 125 workers

• 81.5% of workers

• 97.5% of workers

​ The monthly income of 5000 workers at the Microsoft plant are distributed normally. Suppose the mean monthly income is $1250 and the standard deviation is $250.

Creating a normal distribution curve shows that the amount of workers who earn less than $750 per month is ​ (a)  

• 800 workers

• 125 workers

• 81.5% of workers

• 97.5% of workers