The following data are the magnitudes of earthquakes around the world recorded on January 13,2008.
Because of equipment problems,two earthquakes were unrecorded,although it was known that both had a value less than 2.7.The median magnitude of earthquakes on this date is
A)2.95.
B)3.9.
C)4.0.
D)3.1.
E)This cannot be determined without knowing the exact value of the missing magnitudes.

Question

The following data are the magnitudes of earthquakes around the world recorded on January 13,2008. 
Because of equipment problems,two earthquakes were unrecorded,although it was known that both had a value less than 2.7.The median magnitude of earthquakes on this date is
A)2.95. 
B)3.9. 
C)4.0. 
D)3.1. 
E)This cannot be determined without knowing the exact value of the missing magnitudes.

Quizplus · Accepted Answer

In order to find the median magnitude of earthquakes, we need to arrange the given data in order from smallest to largest. However, we know that there are 2 earthquakes with magnitudes less than 2.7 that were not recorded. Since we do not know their exact values, we cannot include them in our arrangement of the data.

Arranging the given data in order, we have: 
2.7, 3.0, 3.2, 3.2, 3.2, 3.3, 3.4, 3.5, 3.6, 3.8, 4.0, 4.1, 4.2, 4.4, 4.4, 4.5, 4.6

The median magnitude is the middle value, or the average of the two middle values if there are an even number of data points. In this case, there are 17 data points, so the median will be the 9th value (since 8 data points are smaller and 8 data points are larger).

The 9th value in our arranged data is 3.6. Therefore, the median magnitude of earthquakes on January 13, 2008 is 3.6.

None of the answer choices matches this value exactly, but the closest one is D) 3.1. However, this is not the correct answer.

The Following Data Are the Magnitudes of Earthquakes Around the World