Quiz

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.

Find the Z-score.

Mean = 22

Standard Deviation: 3.1

x = 29

• 2.26

• 16.45

• -2.26

• 1.26

Find the mean.

Z-score = -1.25

Standard Deviation: 4

x = 11

• 16

• 6

• 18

• 21

2000 freshmen at State Univ. took a Biology test. The scores were distributed normally with μ=70 and σ=5.

What percent of scores are between 65 and 75?

• 34%

• 50%

• 68%

• 81.5%

What is the standard deviation used in the empirical rule?

• 4

• 2

• 1

• 3

The 75th percentile is also know as the

• median
• third quartile
• 1st quartile`
• interquartile range

The Median is also referred to as

• the 25th Percentile

• the 50th Percentile

• the 75th Percentile

• the 100th Percentile

Find the 46th percentile of this set of 11 values

5, 12, 16, 18, 22, 25, 30, 31, 32, 33, 39

• 5.06

• 5

• 22

• 25

Here are the weights (in pounds) of 10 puppies: 4 4 5 7 8 8 8 10 12 13 What is the percentile of a 5 pound puppy?

• 30th percentile

• 20th percentile

• 70th percentile

• 30th percentile

What shape is a normal distribution curve?

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