CA Foundation · Quantitative Aptitude · Sequence and Series
What is the harmonic mean of 2, 3 and 6?
The harmonic mean is 3. It equals the number of terms divided by the sum of reciprocals. The reciprocals 1/2, 1/3 and 1/6 add up to 1, so the HM is 3 divided by 1, which is 3.
- A3Correct
- B3.5
- C4
- D2.5
Explanation
HM = n / (sum of reciprocals) = 3 / (1/2 + 1/3 + 1/6) = 3 / 1 = 3. Option 3.5 is not the AM (which is 11/3) nor the HM; the distractor 4 would come from wrongly using the arithmetic mean rounded.
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