SOLUTION: Gertrude and Bertha are sisters. They are responsible for keeping the family's driveway clear of snow. If they work together they can complete shoveling in 30 minutes. One day Gert

Question 708632: Gertrude and Bertha are sisters. They are responsible for keeping the family's driveway clear of snow. If they work together they can complete shoveling in 30 minutes. One day Gertrude had to do the job alone. It took her 40 minutes. How long would it have taken Bertha to shovel the same amount alone? You can assume that each girl always shovels at a constant speed.
Answer by josgarithmetic(39617) (Show Source): You can put this solution on YOUR website!
r for rate
t for time in minutes
1 job is "shoveling the snow off the driveway".

Shoveler___________rate_________time____________jobs
Bertha______________r
Gertrude__________1/40
Both______________1/30

Usually one would try to fill in this whole table, but seeing enough information for expressions for rates, and knowing that their rates are additive, we have enough as shown.
, find r, Bertha's rate.
RELATED QUESTIONS
Vern can shovel snow from his driveway in 45 minutes. Nina can do the same driveway in 60 (answered by richwmiller)

Can you help me solve this? Following a severe snowstorm, Ken and Bettina Reeves... (answered by fractalier)

Marvin can shovel the driveway of his family home in 30 minutes. It takes his wife, Nina, (answered by rapaljer)

Janet can shovel snow in her driveway in 65 minutes, Tom can do the same job in 45 mins.... (answered by nerdybill)

Chuck can shovel the snow off his driveway in 40 minutes. He shovels for 20 minutes and... (answered by askmemath)

sue can shovel snow from her driveway in 40 minutes. Jim can do the same job in 50... (answered by Alan3354)

Maria can shovel snow from her driveway in 65 minutes. Tom can do the same job in 45... (answered by scott8148,oberobic)

sue can shovel snow from her driveway in 65 minutes. bill can do the same job in 30... (answered by nerdybill)