Using the following information, determine the sample size needed if the standard time estimate is to be within $10$ percent of the true mean $96$ percent of the time.

$\backslash$table$[[$Work Element,Standard Deviation $($minutes$),$Mean Observed Time $($minutes$)],[1,0\mathrm{.}75,2\mathrm{.}45],[2,0\mathrm{.}15,1\mathrm{.}50],[3,0\mathrm{.}85,3\mathrm{.}80],[4,0\mathrm{.}80,2\mathrm{.}40],[5,0\mathrm{.}60,1\mathrm{.}70],[6,0\mathrm{.}95,2\mathrm{.}45]]$

$($Round up your answer to the next whole number, e$.$g$.150.)$

Sample size needed $$

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