Normal Distribution True/False Questions

The normal curve is symmetrical about the mean.

• True

• False

The area under the normal curve is 1.

• True

• False

Which is NOT true about the normal distribution curve?

• It is bell-shaped.

• The mean, median, and mode are approximately equal

• The smaller the standard deviation, the less spread in the curve.

• It is asymmetrical.

The mean number of accidents a week at a company is 6.4 with a standard deviation of 1.5.  What proportion of weeks would you expect to have less than 5 accidents?

• 0.6915

• 0.1762

• 0.8238

• -0.93

What type of distribution is pictured?

• Right skewed

• Left skewed

• Random

• Normal

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

• 68%

• 95%

• 99.7%

• 50%

How is the graph distributed?

• It is clearly Normal Distribution!

• Slightly skewed to the left.

• Slightly skewed to the right.

• It is clearly Uniform Distribution!

Two measures of center are marked on the density curve shown. Which of the following is correct?

• The median is at the yellow line and the mean is at the red line.

• The median is at the red line and the mean is at the yellow line.

• The mode is at the red line and the median is at the yellow line.

• The mode is at the yellow line and the median is at the red line.

• .

  The mode is at the red line and the mean is at the yellow line.

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 between 12 and 15 days?

• 68%

• 34%

• 16%

• 2.5%

The mean life of a tire is 30,000 km. The standard deviation is 2000 km.

Then, 68% of all tires will have a life between ___________ km and __________ km.

•  28,000 km and 32,000 km.

• 24,000 km and 34,000 km.

• 26,000 km and 34,000 km.

• 27,000 km and 31,000 km.