SOLUTION: Person A takes 6 days less than the time taken by the person B to finish a piece of work. If both A and B together can finish it in 4 days. Find the time that B would take to fin
Algebra ->
Expressions-with-variables
-> SOLUTION: Person A takes 6 days less than the time taken by the person B to finish a piece of work. If both A and B together can finish it in 4 days. Find the time that B would take to fin
Log On
Question 1109378: Person A takes 6 days less than the time taken by the person B to finish a piece of work. If both A and B together can finish it in 4 days. Find the time that B would take to finish this work by himself. Found 2 solutions by stanbon, ikleyn:Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Person A takes 6 days less than the time taken by the person B to finish a piece of work. If both A and B together can finish it in 4 days. Find the time that B would take to finish this work by himself.
------------------
B DATA:
time = x day/job ; rate = 1/x job/day
---
A DATA:
time = x-6 days/job ; rate = 1/(x-6) job/day
------
Together DATA:
time = 4 days/job ; rate = 1/4 job/day
-------
Equation:
rate + rate = together rate
1/x + 1/(x-6) = 1/4
------
4(x-6) + 4x = x(x-6)
8x-24 = x^2 - 6x
x^2 - 14x + 24 = 0
------
x = [14 +-sqrt(14^2 - 4*1*24)]/2
x = 12 days (time for "A" to do the job)
x-6 = 6 days (time for B to do the job alone)
(