Standard Bell curve stats

What is the definition of the mean?

• The average
• The middle number
• The difference between the highest and lowest numbers
• The number that occurs the most

What is the median?

• biggest- smallest
• average
• the middle #
• # that happens the most

What is the range?

• The sum of the largest and smallest number

• The number in the middle

• The difference between the largest and smallest number

• The number that appears most often

What is Standard Deviation?

• A measure of central tendency

• A measurement of how much data varies

• A measurement of how much data varies from the average

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.

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.

Between what two standard deviations of a normal distribution contain 68% of the data?

• one below and one above
• two below and two above
• two below and zero
• zero and two above

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

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

• 68%
• 95%
• 99.7%
• 50%