a work crew of 6 men takes 8 days to complete one - half of a job . if 9 men are then added to the crew and the men continue to work at the same rate , how many days will it take the enlarged crew to do the rest of the job ?
"suppose 1 man can do work in x days . . so 4 men will do in . . 6 / x = 1 / 8 * 1 / 2 as half job is done x = 96 now 9 more are added then 15 / 96 = 1 / 2 * 1 / d for remaining half job d = 3 1 / 5 number of days c"
add(8, divide(multiply(6, 8), add(6, 9)))