SOLUTION: together it takes ann and cindy 2 hr and 24 min to sort recyclable materials. alone ann would require 2 more hours than cindy. how long will it take cindy to do the job alone?
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-> SOLUTION: together it takes ann and cindy 2 hr and 24 min to sort recyclable materials. alone ann would require 2 more hours than cindy. how long will it take cindy to do the job alone?
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Question 888403: together it takes ann and cindy 2 hr and 24 min to sort recyclable materials. alone ann would require 2 more hours than cindy. how long will it take cindy to do the job alone? Answer by lwsshak3(11628) (Show Source):
You can put this solution on YOUR website! together it takes ann and cindy 2 hr and 24 min to sort recyclable materials. alone ann would require 2 more hours than cindy. how long will it take cindy to do the job alone?
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2 hr and 24 min =2.4 hrs
Ann and cindy working together can finish the job in 2.4 hrs
1/2.4=their work rate
let x=hrs cindy can finish the job working alone
1/x=her work rate
x+2=hrs ann can finish the job working alone
1/(x+2)=her work rate
..
sum of indv. work rates=work rate working together
lcd: x(x+2)*2.4
2.4(x+2)+2.4=x(x+2)
2.4x+4.8+2.4=x^2+2x
x^2-0.4x-7.2=0
10x^2-4x-72=0
solve for x by quadratic formula:
a=10, b=-4, c=-10
ans:
x≈2.89 hrs
how long will it take cindy to do the job alone? 2.89 hrs
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