Admission Tests Related Exams
GMAT Exam
If x ≠ 0, for which of the following sets of numbers is the average (arithmetic mean) equal to the median?

In 90 percent of the commercial airline accidents last year, one or another of a group consisting of only 18 percent of the world's commercial airlines was involved. Since the other 82 percent of airlines were generally flying the same types of airplanes as the accident-prone airlines, significant differences in safety procedures must have been responsible for these differences In safety records.
Which of the following, if true about the world's commercial airlines last year, most seriously weakens the argument above?
Last month Ann, Bob, Carl, Dave, and Ellen volunteered at a hospital. The number of hours that Carl volunteered was equal to the average (arithmetic mean) number of hours volunteered by the 5 people. If the number of hours that Carl volunteered was also equal to the total number of hours that Ann and Bob volunteered, then the total number of hours that Dave and Ellen volunteered was how many times the number of hours that Carl volunteered?