Question 968541
Suppose that it takes 9 hours for four workers to roof a house.
 If the time required to do the job varies inversely as the number of people working on it, how long does it take for five workers to finish a
roof of the same size?
:
let t = time required by 5 men to do the job
An inverse relationship
{{{t/9}}} = {{{4/5}}}
Cross multiply
5t = 36
t = 36/5
t = 7.2 hrs fro 5 men to do the job