Instruction 2 -Referring to Instruction 2

question 44

Multiple Choice

Instruction 2.4
The following are the durations in minutes of a sample of long-distance phone calls made within Australia reported by one long-distance carrier.
$$\begin{array} { | l | l | } \hline \text { Time (in Minutes) } & \text { Relative Frequency } \\\hline0 \text { but less than 5 } & 0.37 \\\hline 5 \text { but less than 10 } & 0.22 \\\hline \begin{array} { l } 10 \text { but less than } \\15\end{array} & 0.15 \\\hline \begin{array} { l } 15 \text { but less than } \\20\end{array} & 0.10 \\\hline \begin{array} { l } 20 \text { but less than } \\25\end{array} & 0.07 \\\hline \begin{array} { l } 25 \text { but less than } \\30\end{array} & 0.07 \\\hline 30 \text { or more } & 0.02 \\\hline\end{array}$$
-Referring to Instruction 2.4,if 100 calls were sampled,_________ of them would have lasted 20 minutes or more.

• A) 26
• B) 74
• C) 16
• D) None of the above.

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Definitions:

Dispersion

A statistical measure that describes the spread of or variation in a set of data values.

Variation

The difference in data set values from the mean, highlighting the dispersion or spread of a set of data points.

Quartile

A quartile is a type of statistical measure that divides a data set into four equal parts, revealing the spread and tendencies of the data.

Chebyshev's Theorem

A statistical rule stating for any real number k greater than one, at least (1-1/k^2) of the distribution's values lie within k standard deviations from the mean.