A Work-Sampling Method Is Used to Determine the Proportion of the Time

Multiple Choice

A work-sampling method is used to determine the proportion of the time a worker is idle.The following information was gathered on a random basis.
$$\begin{array} { | c | c | c | } \hline \text { Day } & \begin{array} { c } \text { No. Times } \\\text { Clerk Idle }\end{array} & \begin{array} { c } \text { Total No. } \\\text { Observations }\end{array} \\\hline \text { Monday } & 8 & 26 \\\text { Tuesday } & 8 & 32 \\\text { Wednesday } & 7 & 28 \\\text { Thursday } & 7 & 34 \\\hline\end{array}$$
If the manager wants a 95 percent confidence level and a degree of precision of ± 0.03,how many MORE observations are needed?

A) Fewer than or equal to 700
B) Greater than 700 but fewer than or equal to 800
C) Greater than 800 but fewer than or equal to 900
D) Greater than 900