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The mean of the following scores 30, 32, 34, 36, 38, 40 and 42 What is the mean ...

The mean of the following scores

30, 32, 34, 36, 38, 40 and 42

What is the mean deviation?
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  • A 4.21
  • B 3.24
  • C 3.42
  • D 4.54
Correct Answer: Option C
Explanation:
30, 32, 34, 36, 38, 40, 42 = 7 terms
Assumed mean = \(\frac{30 + 32 + 34 + 36 + 38 + 40 + 42}{7}\)
\(\frac{252}{7}\) = 36
Next we minus each value from the mean (36). Hence we have;
x x - \(\mu\) x - \(\mu\)
30 -6 6
32 -4 4
34 -2 2
36 0 0
38 2 2
40 4 4
42 6 6
Total 24
M.D = \(\sum\) \(\frac{|x - \mu |}{N}\) = \(\frac{24}{7}\) = 3.42

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