<span>Faster maid DATA:
time = x hr/job ; rate = 1/x job/jhr
Slower maid DATA:
time = 3x hr/job ; rate = 1/3x job/hr
Together DATA:
time = 3 hr/job ; rate = 1/3 job/hr
Equation:
rate + rate = together rate
1/x + 1/3x = 1/3
Multiply thru by 3x to get:
3 + 1 = x
x = 4 hrs (time for the faster maid to do the job)</span>
The distance around the bulletin board would be 20 feet, because you multiply 6ft 2x and 4ft 2x.
