Normal Distribution pt1

What shape is a normal distribution curve?

• Half curve
• Round curve
• Bell curve
• Square curve

The normal curve is symmetrical about the mean.

• True
• False

According to the empirical rule, what percentage of data falls within 1 standard deviation of the mean?

• 25%

• 68%

• 95%

• 99.7%

According to the empirical rule, how much of the data falls within 2 standard deviations of the mean?

• 25%

• 68%

• 95%

• 99.7%

If this is the graph of data normally distributed with a mean of 30 and a standard deviation of 5, what label (number) is written at the blue circle?

• 20

• 15

• 40

• 30

The shelf life of a particular dairy product is normally distributed with a mean of 12 days and a standard deviation of 3 days.

About what percent of the products last 6 days or less?

• 68%
• 34%
• 16%
• 2.5%

1.  Which best describes the shaded part of this normal distribution graph?  

• All data that is one or higher.
• All data that is one or more standard deviations above the mean.
• All data that is between 1 and 3.
• All data that is above the mean.

What is the Normal Range (68%) of the annual precipitation for Phoenix, if the average is 29 with a standard deviation of 3?

• 26-32
• 3-29
• 26-29
• 39-32

A standardized test has scores that can be described by a Normal model with a mean score was 100 points and a standard deviation of 10 points. What score is at the 25th percentile?

• 93.26

• 106.74

• 90.32

• 80

Alex's baby was in the 96th percentile for height when she was born. Given σ = 2 inches, and µ = 20 inches, how long was Alex's baby when she was born?

• 23.5 inches

• 20.15 inches

• 17.45 inches

• 37 inches