Measures of Central Tendency and Dispersion of Grouped Data

Measures of Central Tendency help us to relate numbers in a set of data to each other. For example, if the average student’s grade in your math class is an 81, we know that someone who has a grade of 97 is performing well ABOVE the average in that class. Amongst the following choices, which grade would represent a student performance that is considered well BELOW average?

• 80

• 75

• 77

• 62

The following data set represents the responses from students when they were asked how many siblings they had: 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 4, 7 What is the average number of siblings for this set of students?

• About 2.6

• 6

• About 18

• About 2.4

Determine the value of x in the cumulative frequency table below.

• 10

• 11

• 12

• 13

Calculate the standard deviation for the following data.

• 2.928

• 4.848

• 5.148

• 6.227

What is the mode?

• The value that occurs the most often in a data set

• The middle number in an ordered set of data

• The sum of all the numbers in a data set divided by the size

• The sum of the between the greatest and the least elements, divided by two

A data set can have more than one _______

• Median

• Mode

• Mean

• Midrange

Which is the MIDDLE of an ordered set of data?

• Mean

• Median

• Mode

• Range

If you score 76, 85, 97, and 83 on your math tests, what would your median score be? 

• 84

• 90

• 85

• 88

Which is a synonym for "average?"

• mean

• median

• mode

• range

What measure of central tendency (mean, median or mode) would be best for the following set of data?

0, 89, 92, 97, 99, 100

• Mode, because it is the one that shows up the most.

• Median, because there is an outlier. The outlier would influence the mean too much.

• Mean, because you should always use the mean.

• There is not a best measure of central tendency for this data.