Veronica and Trevor, working together but independently at their respective constant rates, can complete a certain job in less than 3 2/3 hours.
Rate * Time = Work Done
Since work done is same throughout the problem so lets take the work done as 1
Let Rate of Veronica = V
Rate of Trevor = T
If they work together then their combined rate will be = V + T
(V+T) * Time = 1
=> Time = \(\frac{1}{V+T}\) < 3\(\frac{2}{3}\)
=> \(\frac{1}{V+T}\) < \(\frac{3*3 + 2}{3}\)
=> \(\frac{1}{V+T}\) < \(\frac{11}{3}\)
=> V + T > \(\frac{3}{11}\) ...(1)
Veronica, working by herself, can complete the job in 5 hours
V * 5 = 1
=> V = \(\frac{1}{5}\)
Trevor can complete the job in t/2 hours , where t is an integer
=> T * \(\frac{t}{2}\) = 1
=> T = \(\frac{2}{t}\)
Substituting in (1) we get
\(\frac{1}{5}\) + \(\frac{2}{t}\) > \(\frac{3}{11}\)
=> \(\frac{2}{t}\) > \(\frac{3}{11}\) - \(\frac{1}{5}\)
=> \(\frac{2}{t}\) > \(\frac{3*5 - 1*11}{11*5}\)
=> \(\frac{2}{t}\) > \(\frac{4}{55}\)
=> t < \(\frac{55}{2}\)
=> t < 27.5
=> Max value of t = 27
So, Answer will be E
Hope it helps!
Watch the following video to MASTER Work Rate Problems