SOLUTION: It takes 12 days for Wallace and Tina to finish the task. It takes 20 days for Wallace alone. How many days does Tina need to complete the task by herself?

Algebra.Com
Question 755532: It takes 12 days for Wallace and Tina to finish the task. It takes 20 days for Wallace alone. How many days does Tina need to complete the task by herself?
Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
1/x + 1/20 = 1/12

20/20x + x/20x = 1/12

(20 + x)/20x = 1/12

12(20 + x) = 20x*1

240 + 12x = 20x

240 = 20x - 12x

240 = 8x

240/8 = x

30 = x

x = 30

So Tina needs 30 days to do the job by herself.

RELATED QUESTIONS

To finish one task, Cathy need 2 more days than Mike.Cathy worked on it for 3 days, then... (answered by ankor@dixie-net.com)
It takes Jose 12 days to complete a task. The same task would take Hans 24 days. After... (answered by mananth)
There is a project. Company A alone needs 20 days to finish. If A works with B, then it... (answered by ankor@dixie-net.com,greenestamps)
If it takes 20 people to complete as task in 12 days. How many people will it take to... (answered by Edwin McCravy)
If it takes 4 days for 6 people to finish a job, than how many days does it take 8 people (answered by stanbon)
There is a project. Company A needs 24 days to finish. Company B needs 30 days to finish. (answered by ikleyn,solver91311,ankor@dixie-net.com,MathTherapy)
How long will it take 20 machines to complete a task, given that it takes 12 days for 5... (answered by rfer)
How many workers will be needed to complete a task in 3 days, given that it takes 10 days (answered by edjones)
Mr. Wallace can paint a fence in 2 hours. His son Greg can paint the fence in 6 hours.... (answered by CharlesG2)