1. Class A and B took a same test. For class A, median score is 80, average score is 82; for class B, median score is 78, average score is 74. Combining A and B, is the average greater than the median?
1). A has 37 students and B has 40 students.
2). A and B have 77 students.
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Average?
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nakulbatra
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cjb
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My guess, in which I have little confidence, is this:nakulbatra wrote:1. Class A and B took a same test. For class A, median score is 80, average score is 82; for class B, median score is 78, average score is 74. Combining A and B, is the average greater than the median?
1). A has 37 students and B has 40 students.
2). A and B have 77 students.
1) This will allow the calculation of the new mean. I have no idea if the new median can be derived form this info, but I would guess not, so insufficient.
2) Won't even allow calculation of mean, so certainly insufficient.
So E, and pray.
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x2suresh
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1)nakulbatra wrote:1. Class A and B took a same test. For class A, median score is 80, average score is 82; for class B, median score is 78, average score is 74. Combining A and B, is the average greater than the median?
1). A has 37 students and B has 40 students.
2). A and B have 77 students.
Average = 82*37+74*40/77 = <78
When you combine two classes.. combined median can't be smaller than smallest median of the two classses.
So median >=78.
Sufficient
2)
We don't know the ratio of Class A:B
Not sufficient
A
