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2 Statistics

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Question 224

For 25 observations, the coded variable z=(x−a)/4z=(x-a)/4z=(x−a)/4 has ∑z=75\sum z=75∑z=75 and ∑z2=321\sum z^2=321∑z2=321. The mean of x x\,x is 52.

a.

Find aaa.

[2]
b.

Calculate the sample standard deviation of xxx.

[4]
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2 Statistics Questions

  1. A Level
  2. /Maths
  3. /2 Statistics

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