A qualified worker digs a well in 6 hours. He invites 2 apprentices, both capable of working 3/4 as fast and 2 trainees both working 1/5 as fast as he. If the five-person team digs the same well, how much time does the team need to finish the job?
Options: A) 1:24 B) 1:34 C) 1:44 D) 1:54 E) 2:14
and answer is correct as you have calculated : 100/64 hrs that is 1.82 hrs - 1 hr and 54 minutes, so 1:54, hence, 1:54.
<result>D</result>
A qualified worker digs a well in 6 hours. He invites 2 apprentices, both capable of working 3/4 as fast and 2 trainees both working 1/5 as fast as he. If the five-person team digs the same well, how much time does the team need to finish the job?