SOLUTION: Hello Tutors! Im working on my chapter review (quadratic functions and equations) and this question stopped my momentum totally. Any help is greatly appeciated. Working together, D

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Hello Tutors! Im working on my chapter review (quadratic functions and equations) and this question stopped my momentum totally. Any help is greatly appeciated. Working together, D      Log On


   

Question 865830: Hello Tutors! Im working on my chapter review (quadratic functions and equations) and this question stopped my momentum totally. Any help is greatly appeciated. Working together, Dani and Cheri can reply to a days worht of customer service e mails in 4 hours. Working alone, Dani takes 6 hours longer than Cheri. How long would it take Cheri alone to reply to these emails?
Im interested in how to set this up, thanks again, may the force be with you!
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
This is a uniform rates of work problem.

The job is, "reply to a days worth of customer emails". That is 1 job. Create expressions or numbers for each worker's work rate as jobs per time. You need to translate from the description into number expressions.

Let x = time in hours for Cheri to do 1 job herself, alone.
Dani, 1%2F%28x%2B6%29
Cheri, 1%2Fx
Dani And Cheri Together, 1%2F4

The rate for both workers "together" is the sum of their individual rates.
highlight_green%281%2Fx%2B1%2F%28x%2B6%29=1%2F4%29.
Solve this equation for x. You WILL obtain a quadratic equation in the solving process. Begin by multiplying the left side and right side by 4x%28x%2B6%29, which is the simplest common denominator; and this will clear the denominators.