bobdylan wrote:If 50 apprentices can finish a job in 4 hrs and 30 skilled workers can finish the same job in 4 1/2 hrs, how much of the job should be completed by 10 apprentices and 15 skilled workers in one hour?
50 apprentices finish the job in 4 hours.
10 apprentices finish the job in (4*5) = 20 hours.
Hence, in 1 hour 10 apprentices finish 1/20 of the job.
30 skilled workers finish the job in 4 and 1/2 hours
15 skilled workers finish the job in (4 and 1/2)*2 = 9 hours
Hence, in 1 hour 15 skilled workers finish 1/9 of the job.
Hence, in 1 hour 10 apprentices and 15 skilled workers finish (1/20 + 1/9) = (9 + 20)/180 = 29/180 of the job.
The correct answer is B.
