The mean and the standard deviation (s.d.) of
10 observations are 20 and 2 resepectively.
Each of these 10 observations is multiplied by
p and then reduced by q, where p $$ \ne $$ 0 and
q $$ \ne $$ 0. If the new mean and new s.d. become
half of their original values, then q is equal to
- A10
- B-20
- C-10
- D-5
✓ Correct answer: B
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