Recognizing Normal Distributions

What shape is a normal distribution curve?

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

The area under a normal distribution

• totals 1.

• is infinite.

• depends on the value of the mean and standard deviation of the data.

• is a z-score.

In a normal distribution,about how much of the curve falls within one standard deviation about the mean?

• 66%

• 68%

• 95%

• 99.7%

The normal distribution is drawn above the

• x-axis.

• y-axis.

• z-axis.

• axis of evil.

The standard normal distribution is drawn above the

• x-axis.

• y-axis.

• z-axis.

• axis of evil.

What is the mean of a standard normal distribution?

• 0

• 1

• the mean of the data

• the standard deviation of the data

The z-score for the mean of any set of normally distributed data is always 0.

• True

• False

The z-score is

• an area.

• a point on a number line.

The weights of adult male beagles are normally distributed, with a mean of 25 pounds and a standard deviation of 3 pounds. A beagle is randomly selected. Find the probability that the beagle’s weight is between 23 and 26 pounds.

• 0.3694
• 0.3781
• 0.0912

The average waist size for teenage males is 29 inches with a standard deviation of 2 inches. 
If waist sizes are normally distributed, determine the z-score of a teenage male with a 33 inch waist.  

• 2
• 1
• -2
• -1