3 machines have a productivity ratio of 1:2:5. all 3 machines are working on a job for 3 hours. at the beginning of the 4th hour, the slowest machine breaks. it is fixed at the beginning at hour 7, and begins working again. the job is done in 9 hours. what was the ratio of the work performed by the fastest machine to the work performed by the slowest?
Say the machines are A, B, and C.nidhis.1408 wrote:3 machines have a productivity ratio of 1:2:5. all 3 machines are working on a job for 3 hours. at the beginning of the 4th hour, the slowest machine breaks. it is fixed at the beginning at hour 7, and begins working again. the job is done in 9 hours. what was the ratio of the work performed by the fastest machine to the work performed by the slowest?
Let us assume that in one hour A, B, and C can do x, 2x, and 5x fractions of the job.
Therefore, A is the slowest machine and C is the fastest.
Now, A has worked for 6 hours and C has worked for 9 hours.
Hence, in 6 hours A has done 6*x = 6x of the job and C has done 9*5x = 45x of the job
Hence, required ratio = 45x/6x = 15/2
