MCQ
If the random error in the arithmetic mean of $50$ observations is $\alpha$, then the random error in the arithmetic mean of $150$ observations would be
- ✓$\frac{\alpha}{3}$
- B$3 \alpha$
- C$\alpha$
- D$2 \alpha$
✓
Answer
Correct option: A.
$\frac{\alpha}{3}$
a
(a)
(a)
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