Tuesday

March 31, 2015

March 31, 2015

Posted by **daisy lebron** on Thursday, September 23, 2010 at 5:57am.

- college algebra -
**Reiny**, Thursday, September 23, 2010 at 8:25amtime for apprentice -- x

time for mason -- x-6

rate of apprentice = 1/x

rate of mason = 1/(x-6)

combined rate = 1l/x + 1/(x-6)

= (2x - 6)/(x(x-6))

then

1/[(2x - 6)/(x(x-6))] = 4

x(x-6)/2x-6) = 4

x^2 - 6x = 8x - 24

x^2 - 14x + 24=0

(x-12)(x-2) = 0

x = 12 or x = 2 , the last makes no sense since x-6 would be negative

so x = 12

the apprentice could build the wall in 12 hours

**Answer this Question**

**Related Questions**

college algebra - 'A mason can build a wall in one-half the time it takes an ...

Algebra - It takes matt 9 hrs longer to build a wall than it takes chris. ...

math - 4 men built a wall in 11 days. How long would it take 1 man to build the ...

Algebra, URGENT!!! - 1) Mio can build a large shed in 15 days less than Yuuko ...

math - John can build 7 birdhouses in 5 hours, write an equation that will allow...

Math - If 600 bricks measuring 12" by 18" are required to build a wall 10 ft. ...

Math-- - A brick layer is hired to build three walls of equal length. He has ...

intermediate Algebra - Mio can build a large shed in 7 days less then yuuko can...

Algebra - Edie can paint a wall in 3 hours. Dan can paint the same wall in 6 ...

algebra - Solve A contractor finds that it takes a crew A 6 hours to construct a...