SOLUTION: Together kim and chris sort recyclables in 2 hours and 55 minutes. Alone it takes kim 2 hours more than chris. How long does it take chris alone ?

Question 412349: Together kim and chris sort recyclables in 2 hours and 55 minutes. Alone it takes kim 2 hours more than chris. How long does it take chris alone ?
Answer by lwsshak3(11628) (Show Source): You can put this solution on YOUR website!
Together kim and chris sort recyclables in 2 hours and 55 minutes. Alone it takes kim 2 hours more than chris. How long does it take chris alone ?
..
let x=minutes Cris takes to complete the job working alone
then 1/x = Chris' minute work rate
x+120=minutes Kim takes to complete the job working alone
then 1/(x+120)= Kim's minute work rate
175 minutes it takes Cris and Kim working together to complete the job
then 1/175 Chris'and Kim's minute work rate working together
sum of individual work rates=work rate working together
(1/x)+1/(x+120)=1/175
LCD=x(x+120)(175)
175(x+120)+175x=x(x+120)
175x+21000+175x=x^2+120x
x^2-230x-21000=0
factor or use quadratic formula to solve:
(x-300)(x+70)=0
x-300=0
x=300 minutes
x+70=0
x=-70 (reject)
ans: It would take Chris 300 minutes to do the job alone

RELATED QUESTIONS
Together, it takes Kim and Chris 2hours and 55minutes to sort recyclables. Alone Kim... (answered by mananth)

Working together, Kim and Chris can paint a room in 3 hours. Working alone, Chris can do... (answered by ikleyn)

together it takes dawn and deb 2 hr 55 min to sort recyclables. alone dawn would require... (answered by ankor@dixie-net.com,MathTherapy)

Together, it takes John and Deb 2 hrs 55 min to sort recyclables. Alone, Jone would... (answered by Alan3354)

Mary and Chris, together can clean their house in 2 hours. Mary alone can clean the house (answered by ptaylor)

I typed the question incorrect the first time, SORRY... Together,it takes John and Deb (answered by ankor@dixie-net.com)

I've been trying to do this problem for days please help me!!! "Dan and Chris can fix the (answered by sudhanshu_kmr)

can some help me figure this out? Together John, Tina and Chris together completes the (answered by scott8148)

help me please? Together John, Tina and Chris together completes the yard in 1 hour and... (answered by scott8148)