SOLUTION: How to solve: Terry the frog and charles the rabbit want to create a course consisting of 30 lessons. If they do it together, it would take them 300 hours. if they do it separately

Algebra ->  Radicals -> SOLUTION: How to solve: Terry the frog and charles the rabbit want to create a course consisting of 30 lessons. If they do it together, it would take them 300 hours. if they do it separately      Log On


   

Question 1011640: How to solve: Terry the frog and charles the rabbit want to create a course consisting of 30 lessons. If they do it together, it would take them 300 hours. if they do it separately, Terry would be 60 hours faster than charles. When they do the job together, how many lessons should terry expect to do? express answer in form of a+b√c
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Work or task rates.
One job is "create the 30 lessons". 

Terry               1/(x-60)

Charles             1/x

Both at same time   1/300


The alternative way is to take the equivalent, Charles needs 60 hours MORE than Terry, and form the rates this way:
Terry               1/x

Charles             1/(x+60)

Both at same time   1/300

Both together, their rates are......
1%2Fx%2B1%2F%28x%2B60%29=1%2F300
.
.
x%5E2-540x-18000=0
.
.
x=%28540%2B-+sqrt%28101%2A100%2A36%29%29%2F2

x=%28540%2B-+60%2Asqrt%28101%29%29%2F2

x=270%2B-+30sqrt%28101%29, but the MINUS form will not make sense.

highlight%28x=270%2B30sqrt%28101%29%29