Question

Below is the five Number summary for a 136 hikers who recently completed the John muir trail JMT the variable is the amount of time to complete the 212 mile Hike from Yosemite Valley across the high sierras To the top of Mount Whitney
5 number summary
Minimum 9 days
Q118 days
Median 21 days
Q328 days
Maximum 56 days

If we use the 1.5 IQR rule to determine whether there are any outliers what is the left a boundary

a. 56
b. 3
c. 43
d. 9

Answer 1

Answer:

$IQR = Q_3 -Q_1 = 28-18 = 10$

Now we can find the limits in order to determine outliers like this:

$Left = Q_1 -1.5 IQR = 18 -1.5*10=3$

$Right = Q_1 +1.5 IQR = 18 +1.5*10=33$

So for this case the left boundary would be 3, if a value is lower than 3 we consider this observation as an outlier

b. 3

Step-by-step explanation:

For this case we have the following summary:

$Minimum = 9$ represent the minimum value

$Q_1 = 18$ represent the first quartile

$Median =Q_2= 21$ represent the median

$Q_3 = 28$ represent the third quartil

$Maximum=56$ represent the maximum

If we use the 1.5 IQR we need to find first the interquartile range defined as:

$IQR = Q_3 -Q_1 = 28-18 = 10$

Now we can find the limits in order to determine outliers like this:

$Left = Q_1 -1.5 IQR = 18 -1.5*10=3$

$Right = Q_1 +1.5 IQR = 18 +1.5*10=33$

So for this case the left boundary would be 3, if a value is lower than 3 we consider this observation as an outlier

b. 3