iran-konkur 2022 Q128

iran-konkur · Other · konkur-riazi_1401_specialized Measures of Location and Spread
128. To estimate the mean income of individuals in a community, we randomly select two samples. We use the standard deviation of the second sample as an estimate for the mean of the first sample, which equals $\frac{2}{\overline{x}}$ times the calculated value for the first sample. The size of the second sample is how many times the size of the first sample?
(1) $1/5$ (2) $2/25$ (3) $2/75$ (4) $3/5$
\textbf{128.} To estimate the mean income of individuals in a community, we randomly select two samples. We use the standard deviation of the second sample as an estimate for the mean of the first sample, which equals $\frac{2}{\overline{x}}$ times the calculated value for the first sample. The size of the second sample is how many times the size of the first sample?

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(1) $1/5$ \hspace{2cm} (2) $2/25$ \hspace{2cm} (3) $2/75$ \hspace{2cm} (4) $3/5$
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