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Interval estimates for proportions — Question 266

Original QCE Vault practice · 1 mark

Q266 · Practice questionTechnology-freeSimple familiar1 mark

QUESTION 266

Using the same confidence level and assumed proportion, a sample of size nn gives a planned margin of error 0.040.04. To reduce this to 0.020.02, the required sample size is
(A)
8n8n
(B)
4n4n
(C)
n2\dfrac n2
(D)
2n2n
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