We define the average (harmonic mean) as the reciprocal of the average

Question

We define the average (harmonic mean) as the reciprocal of the average (arithmetic mean) of reciprocals. What is the average (harmonic mean) of 2, 3, and 6?
 
A. 1/3 
B. 1/2 
C. 1 
D. 2 
E. 3

banuchandar · Answer

Harmonic mean = 1/A

A ==> Average of the reciprocals of 2, 3 and 6 = (1/2 + 1/3 + 1/6)/3 = 1/3

Hence H = 3 Answer option E.

sashiim20 · Answer

Average (Arithmetic mean) of reciprocals of 2,3 and 6 =  (\frac{1}{2} + \frac{1}{3} + \frac{1}{6}) /3  =  (\frac{3+2+1}{6})/3  =  (\frac{6}{6})/3  =  \frac{1}{3}

Harmonic mean is the reciprocal of the average (arithmetic mean) of reciprocals =  \frac{3}{1}  = 3 
Answer E...

dabhishek87 · Answer

\frac{1}{2} + \frac{1}{3} + \frac{1}{6} = 
\frac{3}{h} 
h = 3, answer E

MathRevolution · Answer

==> If you find the average of the reciprocals, you get  \frac{++}{3}=\frac{1}{3}  .

Since it is the reciprocal of that, the answer is E.
Answer: E

amanvermagmat · Answer

Reciprocal of the - average of reciprocals.

So lets take average of reciprocals first. (1/2 + 1/3 + 1/6)/3 = (6/6)/3 = 1/3

Now lets take its reciprocal. 1/(1/3) = 3. hence  E answer

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We define the average (harmonic mean) as the reciprocal of the average

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We define the average (harmonic mean) as the reciprocal of the average

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