Question 139279
6 workers
1/2 job
12 days


So:
6 workers
{{{(1/2)(1/12)=1/24}}} job in 1 day


So:
1 worker
{{{(1/24)(1/6)=1/144}}} job in 1 day


1/2 job
4 days
means 1/8 job in 1 day


To do 1/8 job in 1 day, you need {{{(1/8)/(1/144)=144/8=18}}} workers.