# COMPARING BOX PLOTS

Comparing box plots :

We can compare two box plots numerically according to their centers, or medians, and their spreads, or variability. Range and interquartile range (IQR) are both measures of spread.

Box plots with similar variability should have similar boxes and whiskers.

Box plots with greater variability, where there is less overlap of the median and interquartile range.

## Box plots with similar variability - Example

The box plots show the distribution of times spent shopping by two different groups.

1.  Compare the shapes of the box plots.

The positions and lengths of the boxes and whiskers appear to be very similar. In both plots, the right whisker is shorter than the left whisker.

2.  Compare the centers of the box plots.

Group A’s median, 47.5, is greater than Group B’s, 40. This means that the median shopping time for Group A is 7.5 minutes more.

3.  Compare the spreads of the box plots.

The box shows the interquartile range. The boxes are similar.

Group A: 55 - 30 = 25 min Group B: About 59 - 32 = 27 min

The whiskers have similar lengths, with Group A’s slightly shorter than Group B’s.

4.  Which group has the greater variability in the bottom 50% of shopping times ? The top 50% of shopping times ? Explain how you know.

Group A; Group B; look at which box plot has a greater distance from the median to the minimum or maximum value, respectively.

## Box plots with different variability - Example

The box plots show the distribution of the number of team wristbands sold daily by two different stores over the same time period.

1.  Compare the shapes of the box plots.

Store A’s box and right whisker are longer than Store B’s.

2.  Compare the centers of the box plots.

Store A’s median is about 43, and Store B’s is about 51. Store A’s median is close to Store B’s minimum value, so about 50% of Store A’s daily sales were less than sales on Store B’s worst day.

3.  Compare the spreads of the box plots.

Store A has a greater spread. Its range and inter quartile range are both greater.

Four of Store B’s key values are greater than Store A’s corresponding value.

Store B had a greater number of sales overall.

After having gone through the stuff given above, we hope that the students would have understood "How to compare box plots".

Apart from the stuff given in this section, if you need any other stuff in math, please use our google custom search here.

You can also visit our following web pages on different stuff in math.

WORD PROBLEMS

Word problems on simple equations

Word problems on linear equations

Algebra word problems

Word problems on trains

Area and perimeter word problems

Word problems on direct variation and inverse variation

Word problems on unit price

Word problems on unit rate

Word problems on comparing rates

Converting customary units word problems

Converting metric units word problems

Word problems on simple interest

Word problems on compound interest

Word problems on types of angles

Complementary and supplementary angles word problems

Double facts word problems

Trigonometry word problems

Percentage word problems

Profit and loss word problems

Markup and markdown word problems

Decimal word problems

Word problems on fractions

Word problems on mixed fractrions

One step equation word problems

Linear inequalities word problems

Ratio and proportion word problems

Time and work word problems

Word problems on sets and venn diagrams

Word problems on ages

Pythagorean theorem word problems

Percent of a number word problems

Word problems on constant speed

Word problems on average speed

Word problems on sum of the angles of a triangle is 180 degree

OTHER TOPICS

Profit and loss shortcuts

Percentage shortcuts

Times table shortcuts

Time, speed and distance shortcuts

Ratio and proportion shortcuts

Domain and range of rational functions

Domain and range of rational functions with holes

Graphing rational functions

Graphing rational functions with holes

Converting repeating decimals in to fractions

Decimal representation of rational numbers

Finding square root using long division

L.C.M method to solve time and work problems

Translating the word problems in to algebraic expressions

Remainder when 2 power 256 is divided by 17

Remainder when 17 power 23 is divided by 16

Sum of all three digit numbers divisible by 6

Sum of all three digit numbers divisible by 7

Sum of all three digit numbers divisible by 8

Sum of all three digit numbers formed using 1, 3, 4

Sum of all three four digit numbers formed with non zero digits

Sum of all three four digit numbers formed using 0, 1, 2, 3

Sum of all three four digit numbers formed using 1, 2, 5, 6