Q3 · 2024 · Technology-freeSimple familiar1 mark
QUESTION 3
If the confidence level of a confidence interval is increased while the sample data are unchanged, what happens to the -value and the margin of error?
(A)
the associated z-value would decrease, so E would increase.
(B)
the associated z-value would increase, so E would increase.
(C)
the associated z-value would decrease, so E would decrease.
(D)
the associated z-value would increase, so E would decrease.
WORKED SOLUTION
1 markAnswer B
ANSWER
B — the associated z-value would increase, so E would increase.
Worked solution
Increasing confidence increases the critical -value, so with the same standard error the margin of error increases; B.
Selects option B.
Worked explanation by QCE Vault; correct option verified against the QCAA answer key.
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