Party trays which cost $14.00 to make not including labor are sold for $35.00. if two people work 8-hour shifts making the trays at $7.00 per hour, how many trays must be sold to cover all costs including labor?

Profit on each tray sold excluding labor cost

= $35-$14

= $21

Total labor cost for making party tray for a day

Total labor hours * wages per hour * No. of labors

= $7 * $8*2

= $112

Number of trays must be sold to cover cost will be:

= Total labor cost for making party tray for a day / Profit on each tray sold excluding labor cost

= $112/$21

= 5.33

5.33 trays must be sold to cover all costs including labor.