Two different liquid filter systems are being studied to clarify a

liquid stream. A traditional filter will operate for one $8-$hour

shift before being replaced $(3$ shifts per day and $5$ days per

week$).$ A special pleated design can last one full week,

operating $24$ hours a day $(3$ shifts$),5$ days per week. Labor cost

to change a filter is estimated to be worth $$10\mathrm{.}00$ for each

filter change because a mechanic would work overtime to

change the filter. The traditional filters cost $$3\mathrm{.}50$; the special

pleated filters cost $$90\mathrm{.}00.$ Which filter should be chosen?

$26$