| Work problems Jim can mow Mr.Smith's lawn in 6 hours, Bob can mow Mr.Smith's lawn in 4 hours. How long would it take them to mow the yard if they worked together?
Just to get you started:
Jim can do 1/6 of the job per hour, Bob can do 1/4 of the job per hour. So together they can do 1/6 + 1/4 of the job per hour.
Is that enough of a hint? |