Question 995321
Let x=time it takes less experienced person
Then this person works at the rate of 1/x of the task per hour
It takes the more experienced person (x-1) hours to complete the task
Then this person works at the rate of 1/(x-1) of the task per hour
Together, it takes 1.2 hours to complete the task
So together they work at the rate of 1/(1.2) of the task per hour
We also know that together they work at the rate of 1/x + 1/(x-1) of the task per hour
So our equation to solve is:
1/x + 1/(x-1)=1/(1.2)  Multiply each term by (1.2)x(x-1)
This reduces to:
x^2-3.4x+1.2=0  quadratic in standard form and it can be factored
(x-3)(x-0.4)=0
x=3 and
x=0.4---an hour less than this is negative hours
ANS:Less experienced person takes 3 hrs
more experienced person takes 2 hrs
CK
1/3+1/2=1/(1.2)=10/12
4/12 + 6/12= 10/12
10/12=10/12

Hope this helps---ptaylor