Stats Concepts

How can we describe the distributions?

• The distribution for Driver A is skewed left and the distribution for Driver B is close to symmetric.

• Both distributions are skewed left.

• The distribution for Driver A is skewed right and the distribution for Driver B is close to symmetric.

• Both distributions are skewed right.

Which statement is not true?

• The median for the length of grey squirrels is equal to that of red squirrel lengths.

• The median for the length of grey squirrels is greater than 75% of red squirrel lengths.

• Approximately 25% of red squirrel lengths are less than the minimum length of grey squirrels.

Which statement should NOT be included when describing the distribution of the number of magazines sold?

• The most common number of magazines sold was 20 magazines.

• There are gaps where no data is present.

• The gaps in the data signify outliers.

• The number of magazines sold ranges from 17 to 25 magazines.

Which statement best describes this graph?

• There is a peak at 47.

• There is a cluster around 38-40.

• The mode is 40.

• There is a gap in the data between 39-40.

What is the standard deviation for the data given:

5, 10, 7, 12, 0, 20, 15, 22, 8, 2

• 6.89

• 10.1

• 7.26

• 9

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

• 68%

• 95%

• 99.7%

• 50%

Find the mean of these numbers:
5,11,2,12,4,2

• 4.1

• 6

• 4.5

• 4

What is the mean?

• happening the most

• the number in the middle

• biggest-smallest

• the average

What is the median?

• biggest- smallest

• average

• the middle #

• # that happens the most

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.