Question 663495
 Miguel works 3 times faster than Steven.
 Together they do a job in 9 hours. 
 How long does it take Steven working alone to do the same job?
:
Let t = time required by M to do the job
then
3t = time required by S
:
Let the completed job = 1
:
{{{9/((3t))}}} + {{{9/t}}} = 1
multiply by 3t, results:
9 + 3(9) = 3t
9 + 27 = 3t
36 = 3t
 t = 36/3
 t = 12 hrs for M to do the job
but they want how long it took S:
3(12) = 36 hrs for S to do it
: