Problema Solution
Ramon can paint a fence in two hours. Jenny can paint the same fence 15 minutes faster than Ramon and Dennis can paint it in half Ramon's time. About how many minutes will it take to paint the fence if all three people work together?
I got approx. 29 minutes. The book says that the answer is 60. How can this be?
Answer provided by our tutors
Jenny can paint the same fence 15 minutes faster than Ramon and Dennis can paint it in half Ramon's time. About how many minutes will it take to paint the fence if all three people work together?
First, figure out individual "timings"
(using initiall of "painters" as time spent on work in minutes:)
R=2=120
J=R-15 =105
D=R/2 =60
These three together will spend T minutes on work with
1/T=1/120+1/105+1/60= 28.97 min or approximately 29 minutes:
this is it!