Question 225673
they each do a FRACTION of the job based on their individual times and the combined time


FRACTION equals combined/individual ___ the FRACTIONS sum to 1, the WHOLE job


let x="combined time"


x/2 + x/4 + x/6 = 1


multiplying by 12 (LCD) ___ 6x + 3x + 2x = 12 ___ 11x = 12


dividing by 11 ___ x = 12/11