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Find the variance of the distribution $x = 1$ , 2, 3, 4, 5 with frequencies 2, 3, 5, 3, 2.

Competition practiceStatistics

A4.4
B1.47
C1.21
D1.57

Step-by-Step Solution

N = 15

, mean = 3 (the table is symmetric).

Σ f (x - 3)^{2} = 8 + 3 + 0 + 3 + 8 = 22

; variance

= \frac{22}{15} \approx 1.47

. (1.21 is the SD; 4.4 divides by the 5 rows.)

Answer: B) 1.47

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