Pearson Algebra 1 Common Core, 2011
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Pearson Algebra 1 Common Core, 2011 View details
4. Box-and-Whisker Plots
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Exercise 15 Page 750

Arrange the data from least to greatest before identifying the minimum, maximum, and quartiles. You will need these values to make the box-and-whisker plot.

Camera Prices

Practice makes perfect

We want to identify the minimum, first quartile, median, third quartile, and maximum of the given data set. Then we will make a box-and-whisker plot using these values. Let's do these things one at a time.

Values

Quartiles are values that divide a data set into four equal parts. When quartiles are combined with the minimum and maximum values, it is often called the five-number summary of the data set.

  • The median, which can also be known as the second quartile (Q_2), separates the data into upper and lower halves.
  • The first quartile (Q_1) is the median of the lower half of the data.
  • The third quartile (Q_3) is the median of the upper half of the data.

Let's identify the five-number summary of the given data set. Do not forget to arrange the data from least to greatest first! Given Data Set $280 $220 $224 $70 $410 $90 $30 $120 Arranged Data Set $30 $70 $90 $120_(lower half) $220 $224 $280 $410_(upper half) The minimum and maximum values are $30 and $410, respectively. Since the number of values is even, the median is the average of the two middle values. Median: $120+ $2202= $170 Moreover, the number of values in each half is even, therefore the first quartile is the average of the two middle values in the lower half. Q_1: $70+ $902= $80 Analogously, the third quartile is the average of the two middle values in the upper half. Q_3: $224+$2802=$252 The first quartile is $80 and the third quartile is $252.

Box-and-Whisker Plot

We want to make a box-and-whisker plot using the obtained information. Minimum:& $30 First Quartile:& $80 Median:& $170 Third Quartile:& $252 Maximum:& $410 This type of graph summarizes a set of data by displaying it along a number line. It consists of three parts, a box and two whiskers.

  • The left whisker extends from the minimum to the first quartile.
  • The box extends from the first to the third quartile and has a vertical line through the median.
  • The right whisker extends from the third quartile to the maximum.

Let's make our box-and-whisker plot! Camera Prices (dollars)