Question

Find the harmonic mean of 3, 6 and 10.
1. 6.33
2. 5
3. 5.6
4. 4.5

Answer 1

Correct Answer - Option 2 : 5

Given

Observations = 3, 6, 10

Formula used

Harmonic mean = n/Σ1/x_i where i = 1, 2, 3, 4 ------

n = number of observation

x = observations value

Calculation

x_i = 3, 6, 10

⇒ Σ1/xi  = 1/3 + 1/6 + 1/10 = 3/5

⇒ number of observation = 3

⇒ Harmonic mean  = 3/3/5 = (3 × 5)/3

∴ Harmonic mean = 5

The harmonic mean it is defined as the reciprocal  of the arithmetic mean of the observations of a set

Harmonic mean = n/Σ1/xi where i = 1, 2, 3, 4 ------

n = number of observation

x = observations value

Geometric mean = it  is defined as the n-th root of the product of the n observations.

GM = n(√x₁ × x₂--------x_n)