Bunuel wrote:
Tough and Tricky questions: Work/Rate Problems.
A group of 4 junior lawyers require 5 hours to complete a legal research assignment. How many hours would it take a group of three legal assistants to complete the same research assignment assuming that a legal assistant works at two-thirds the rate of a junior lawyer?
A) 13
B) 10
C) 9
D) 6
E) 5
Kudos for a correct solution.Source: Chili Hot GMAT
one hr work of 4 lawyers is 1/5
then one hr work of 1 lawyer will be 1/20
given that assistant works at two-thirds the rate of a junior lawyer
therefore in one hr an assistant will complete 2/3 of 1/20 i.e 1/30 of work
then one hr work of a group of 3 assistants will be 3* 1/30 = 1/10
thus a group of 3 assistant will complete the work in 10 hours
[B]
_________________
Never Try Quitting, Never Quit Trying