Question

Fernando and Kevin are delivering microwave ovens to a local appliance store, whose freight elevator can hold no more than 900 pounds. If Fernando weighs 180 pounds, Kevin weighs 240 pounds, and the microwave ovens weigh 30 pounds each, how many microwaves can Fernando and Kevin deliver at one time if they must ride in the elevator as well?

Answer 1

well, the elevator is ok with 900lbs

once Fernando steps in, there's 180lbs
then Kevin steps in too, there's 240lbs more

so the elevator with only both guys is already taking 180+240lbs of weight off the 900 it can take

so whatever is left, 900-180-240, is how many lbs the elevator can take
divide that by 30 and get the amount of microwaves they can carry