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Question
The standard deviation of a data is 3. If each value is multiplied by 5 then the new variance is
Options
3
15
5
225
Solution
225
Explanation;
Hint:
σ = 3
If each is multiplied by 5
The new standard variation is also multiplied by 3
∴ The new S.D = 5 × 3 = 15
Variance = 152 = 225
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