1. The following graph of a normal distribution has a mean of 20 and a standard deviation of 5.
[attachment=2:30r8pltm]8-4_quiz_curve1_cbel.gif[/attachment:30r8pltm]
What percent of the data lies between 15 and 25?
2. The following graph of a normal distribution has a mean of 8 and a standard deviation of 1.5.
[attachment=1:30r8pltm]8-4_quiz_curve2_cbel.gif[/attachment:30r8pltm]
What percent of the data is greater than 6.5?
3. The scores for a particular examination are normally distributed with a mean of 59.6% and a standard deviation of 9.2%. What is the probability that a student who wrote the examination had a mark of 70% or less? Give your answer to the nearest hundredth.
4. The following graph of a normal distribution has a mean of 75 and a standard deviation of 5.
[attachment=0:30r8pltm]8-4_quiz_curve6_cbel.gif[/attachment:30r8pltm]
which of the following apply to how the shape and location of the curve would change if the mean becomes 80 and the standard deviation changes to 3.
shifted left
shifted right
narrower
broader
same location
same shape
[attachment=2:30r8pltm]8-4_quiz_curve1_cbel.gif[/attachment:30r8pltm]
What percent of the data lies between 15 and 25?
2. The following graph of a normal distribution has a mean of 8 and a standard deviation of 1.5.
[attachment=1:30r8pltm]8-4_quiz_curve2_cbel.gif[/attachment:30r8pltm]
What percent of the data is greater than 6.5?
3. The scores for a particular examination are normally distributed with a mean of 59.6% and a standard deviation of 9.2%. What is the probability that a student who wrote the examination had a mark of 70% or less? Give your answer to the nearest hundredth.
4. The following graph of a normal distribution has a mean of 75 and a standard deviation of 5.
[attachment=0:30r8pltm]8-4_quiz_curve6_cbel.gif[/attachment:30r8pltm]
which of the following apply to how the shape and location of the curve would change if the mean becomes 80 and the standard deviation changes to 3.
shifted left
shifted right
narrower
broader
same location
same shape
