SOLUTION: Danielle can harvest a field in 16 hours. Kathryn can harvest the same field in 12 hours. Find how long it would take them if they worked together.

Algebra ->  Customizable Word Problem Solvers  -> Misc -> SOLUTION: Danielle can harvest a field in 16 hours. Kathryn can harvest the same field in 12 hours. Find how long it would take them if they worked together.       Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


   



Question 715146: Danielle can harvest a field in 16 hours. Kathryn can harvest the same field in 12 hours. Find how long it would take them if they worked together.
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
Let the answer be x.  That is, it would take them x hours if they worked together. 
So their harvesting rate is 1 field per x hours, %221_field%22%2F%22x_hr%22 or 1%2Fxfield%2Fhour.

Danielle can harvest a field in 16 hours.
So Danielle's harvesting rate is 1 field per 16 hours, %221_field%22%2F%2216_hr%22 or 1%2F16field%2Fhour.

Kathryn can harvest the same field in 12 hours.
So Kathryn's harvesting rate is 1 field per 12 hours, %221_field%22%2F%2212_hr%22 or 1%2F12%7D%7D%7B%7B%7Bfield%2Fhour.

Find how long it would take them if they worked together.
The equation comes from
  
               %22%22%2B%22%22%22%22=%22%22 

                              1%2F16%22%22%2B%22%221%2F12%22%22=%22%221%2Fx

Multiply that equation through by the LCD = 48x  and solve for x and you'll 
get 48%2F7 or 6%266%2F7 hours.

Edwin