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The dot plot shows how many pupils were absent on each of 10 school days. Find the mean deviation about the mean.

Competition practiceStatistics

A0.8
B1.1
C1.6
D4

Step-by-Step Solution

Absences: 1 (1 day), 2 (2 days), 3 (4 days), 4 (2 days), 5 (1 day); mean

= 3.Σ f ∣ x - 3∣ = 2 + 2 + 0 + 2 + 2 = 8

; MD

= \frac{8}{10} = 0.8

. (1.1 is the SD.)

Answer: A) 0.8

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