Five workers have been hired to complete a job. If one additional worker is hired, they could complete the job $8$ days earlier. If the job needs to completed $28$ days earlier, how many additional workers should be hired?
D==Number of days needed for 5 workers to finish the job.
W==Number of additional workers needed
5D ==6[D - 8].......................(1)
5D / [5 + W]==48 - 28.......(2), solve for D, W
Use substitution to get:
D ==48 days
W==7 additional workers needed
5 + 7 ==12 workers in total will be needed.