# algebra

posted by .

lean can paint her new apartment 3 hours longer than his friend,carlos.if both can do painting in 2 hours,how long will it take each one to finish the job alone?

• algebra -

labour*time=job time=job/labour
time=3 and 3x=1 x=1/3
If both can do painting in 2 hours,So
(x+y)2=1 x=1/3 hence (1/3+y)*2=1
And y is 1/6.We can say that it take 6hours to finish the job alone.

• algebra -

let Carlos' time be x hrs
so rate for Carlos = 1/x
Lean's time is x+3
Lean's rate = 1/(x+3)

combined rate = 1/x + 1/(x+3)
= (x+3 + x)/(x(x+3)) = (2x+3)/(x(x+3))

1/[ (2x+3)/(x(x+3))] = 2
x(x+3)/(2x+3) = 2
x^2 + 3x = 4x + 6
x^2 - x - 6 = 0
(x-3)(x+2) = 0
x = 3 or x=-2, the latter is not possible

Carlos would take 3 hrs, and Lean would take 6 hrs alone

check:
combined rate = 1/3 + 1/6 = 1/2
combined time = 1/(1/2) = 2

• algebra -

Keiko bicycles 4km/h faster than Carlos. In the same time it takes Carlos to Bicycle 45km, Keiko can bicycle 57km. How fast does each bicyclist travel?

## Similar Questions

1. ### math

1.a collection of 105 coins consists of 1 peso and 5 pesos. if the total value is 205 pesos, find the number of coins of each denomination in the collection. 2.leslie's wallet contains 20 peso bills and 1 peso coins with a total of …
2. ### algebra2/trig

tina can paint a room in 8 hours, but when she and her friend emily work together, they can complete the job in 3 hours. how long would it take emily to paint the room alone?
3. ### College Algebra

It takes Todd 3 hours longer than Tom to paint a 4x5 feet bedroom. Working together, both can complete the job in two hours.How long does it take each one to complete the painting job working alone?
4. ### algebra

you can paint a room in 8 hours. your friend and you can paint a room in 5 hours together. how long does it take your friend alone?
5. ### algebra 2/trig

Tina can paint a room in 8 hours, but when she and her friend Emily work together, they can complete the job in 3 hours. How long would it take Emily to paint the room alone?
6. ### math

May takes 12 hours to type a report. Her friend helps her and together they finish the job in 4 hours. How long would it take her friend had she worked alone?
7. ### Math

when linda and martin work together painting one room, they can complete the work in 5 hours. when linda works alone it takes her 7 hours to paint the same room. how long would it take marvin to paint the room alone?
8. ### Algebra

Tom and Jerry are working together to weed the garden. Working together it takes them 2 hours and 24 minutes. If it takes Tom two hours longer to finish the job alone than it takes Jerry to finish the job alone, how long would it take …
9. ### Algebra

Ann, Matt and Zack are working for a cleaning company. Together, they can clean a house in 2 hours. If Ann does the job alone she can finish it in 5 hours. If Matt does the job alone he can finish it in 6 hours. How long will it take …
10. ### Math

Alice can complete a certain job in 5 hours she had been working on the job for two hours when a friend came along. And helped her finish together they completed the job in 1 hr how long would it take alices friend to complete a job …

More Similar Questions