The data in the following table represent time$-$study observations on a new operation with three work elements. On the basis of these observations, find the standard time for the process. Assume a $15\%$ allowance factor.

Observations $($times in seconds$)$

Element

Performance Rating

$2$

$3$

$4$

$1$

$120\%$

$90\mathrm{.}3$

$91\mathrm{.}5$

$92\mathrm{.}4$

$90\mathrm{.}2$

$2$

$100\%$

$30\mathrm{.}5$

$32\mathrm{.}3$

$29\mathrm{.}6$

$31\mathrm{.}1$

$3$

$105\%$

$130\mathrm{.}5$

$128\mathrm{.}9$

$132$

$130\mathrm{.}5$