SOLUTION: it takes jack 3.5 hours to complete a job and it takes 2 hours for eleanor to do the same job. How long would it take for them to complete the job working together?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: it takes jack 3.5 hours to complete a job and it takes 2 hours for eleanor to do the same job. How long would it take for them to complete the job working together?      Log On


   

Question 684008: it takes jack 3.5 hours to complete a job and it takes 2 hours for eleanor to do the same job. How long would it take for them to complete the job working together?
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = time it takes them to do the job together.

1%2F3.5%2B1%2F2+=+1%2Fx

First fraction is UGLY, so multiply numerator and denominator by 2 to clear the decimal:

2%2F7+%2B+1%2F2+=+1%2Fx

Next, add the fractions with LCD = 14:
4%2F14+%2B+7%2F14+=+1%2Fx

11%2F14=1%2Fx

Invert the fractions:
14%2F11+=+x%2F1
x= 14/11 hours

Dr. Robert J. Rapalje, Retired
Seminole State College of Florida

www.mathinlivingcolor.com.