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Find the variance of 42, 24, 32, 64, 68?

  1. 312.4
  2. 300.8
  3. 306.6
  4. 308.2

Answer (Detailed Solution Below)

Option 2 : 300.8
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Detailed Solution

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GIVEN:

Five numbers 42, 24, 32, 64, 68

CONCEPT:

Concept of variance

FORMULA USED:

Mean = Sum/Total

Variance (σ2) = ∑δ2/n

CALCULATION:

Mean = (42 + 24 + 32 + 64 + 68)/5 = 230/5 = 46

∑δ2 = |42 - 46|2 + |24 - 46|2 + |32 - 46|2 + |64 - 46|2 + |68 - 46|2

⇒ 16 + 484 + 196 + 324 + 484

⇒ 1504

Variance (σ2) = ∑δ2/n

⇒ 1504/5

= 300.8

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