Question

Fourteen different second-year medical students at a hospital measured the blood pressure of the same person. The systolic readings (mm Hg) are listed below. Use the given data to construct a boxplot and identify the 5-number summary. 124 132 135 R 139 139 120 120 125 125 135 135 130 145 R 134 140 131 130 R 145 148 150 The 5-number summary is 1,0,,1, and , all in mm Hg. (Use ascending order. Type integers or decimals. Do not round.) Which boxplot below represents the data? ОА. OB. O O 120 130 140 150 120 130 140 150 O Blood Pressure (mm Hg) Blood Pressure (mm Hg) Ос. OD. O O -EE 120 130 140 150 m 120 130 140 150 S Blood Pressure (mm Hg) Blood Pressure (mm Hg)

Answer 1

• Five number summary:

Answer : The 5 number summary is 120 , 130 , 134.5 , 140 and 150

• Box plot :

Answer : Option ( D )

Explanation :

The minimum value of the data set is 120.

The first quartile (or lower quartile or 25th percentile) is the median of the bottom half of the numbers. So, to find the first quartile, we need to place the numbers in value order and find the bottom half.

120   124   125   130   131   132   134   135   135   139   140   145   148   150   

So, the bottom half is

120   124   125   130   131   132   134   

The first quartile of the data set is 130.

The median is the middle number in a sorted list of numbers. So, to find the median, we need to place the numbers in value order and find the middle number.

Ordering the data from least to greatest, we get:

120   124   125   130   131   132   134   135   135   139   140   145   148   150   

As you can see, we do not have just one middle number but we have a pair of middle numbers, so the median is the average of these two numbers:

Median = ( 134+135 ) / 2 = 134.5

The median of the data set is 134.5.

The third quartile (or upper quartile or 75th percentile) is the median of the upper half of the numbers. So, to find the third quartile, we need to place the numbers in value order and find the upper half.

120   124   125   130   131   132   134   135   135   139   140   145   148   150   

So, the upper half is

135   135   139   140   145   148   150   

The third quartile of the data set is 140.

The maximum value of the data set is 150.