Statistics in Math =]

By: Jessica Laura and Daniel Mole’

The Average

It is smarter to stay away from this sometimes unclear term. It usually relates to the (arithmetic) mean. It can also indicate the mode, median, the

weighted means, or the geometric mean, including many others.

Histograms

A Histogram, in which the area of each bar’s interval is not there. The bars are connected and it shows a difference between each

set of data.

The photo to the right is an example of a histogram.

The Mean

The mean is the total of the data divided by the total amount of numbers in the set. Also called arithmetic

mean.

Example: What is the mean of this set of numbers? 2, 4, 6, 8, 10.

First, you have to add the numbers together, getting 20. Then, you must divide 20 by the amount of numbers in

the set (which is five). The mean comes out to be 4.

The MedianThe median is the middle value in a set of data. If the list has an odd

number of values, the median is the middle entry in the set, after arranging the list into a rising order. If the list has an EVEN amount of values, the median comes out to be both the sum of the two numbers divided by 2. The median can also be estimated using a histogram.

Example: What is the median in this set of numbers? 2, 8, 9, 12, 4, 5, 6, 6, 10, 6.

First, we have to put the numbers into increasing order. It comes out to be 2, 4, 5, 6, 6, 6, 8, 9, 10, 12. We have to find the number located

in the middle. The median is 6.

The Mode

For all lists, the mode is really the number that appears the most. A list can have over one mode. A list has no mode when every number comes up with the same

frequency. A list has more than one mode when two or more numbers come up with the same frequency.

Example: Find the mode in this set of numbers:2, 3, 6, 7, 8, 11, 13, 2, 4, 2. The mode is 2, since it appears

three times.

Multimodal Distribution

A distribution with a mode greater than one. The histogram of a multimodal distribution has more than

one “bump”.

A bump is the difference between two bars in a histogram.

The Range

The range in a set of data is the smallest number subtracted from the greatest number. The range is a

single number, not several numbers.

Example: What is the range in this set of numbers? 64, 99, 82, 73, 58. The range is equal to 99 – 58,

which is equal to 41.

Total

The total is the total number of the sum. It is equal to all the numbers in the set added together.

Example: What is the total of this data set? 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. We have to add them all together,

which comes out to be 55.

Get to Work

James and his friends compared state wide test

scores. Jon got a 735, Danielle got a 675, Jamie got a 650, Amy got a 790, Jessica got a 790, Danny

got a 625, and James got a 780.

Range: ___

Mean: ___

Median: ___

Mode: ___

Total: ___

Make a Histogram: ___

Answers

Range: 165

Median: 735

Mean: About 609

Mode: 790

Total: 5,020

Jon

Danielle

Jamie

Amy

Jessica

Danny

James

0200400600800

1000

Test Scores

Students

Score

s

Bibliography

www.shodor.org/interactivate/lessons/introstatistics

7th grade Impact Math Copyright 2009

www.easycalculation.com/statistics/mean-median-mode.php