Question 1199268
Jay can do a painting job in 2/3 as many days as Chris can,
 and Chris can do it in 3/4 as many days as Araceli can.
 If all three work together, they can do it in 36/13 days.
 In how many days can each of them alone do the work?
:
let a = time required by A do the job
then
(2/3)*(3/4) = (1/2)a = J's time to do the job
and
(3/4)a = C's time
We can use decimals with these two fractions, .5 and .75 (less tedious)
lets try using 36/13 = 2.77 for time working together
let 1 = the completed job
{{{2.77/(.5a)}}} + {{{2.77/(.75a)}}} + {{{2.77/a}}} = 1 
multiply by 3a, cancel the denominators, gets rid of the fractions 
6(2.77) + 4(2.77) + 3(2.77) = 3a 
16.62 + 11.08 + 8.31 = 3a
totals 36.01,round it down to 36
3a = 36
a = 12 hrs is A's time
then
.5(12) = 6 hrs is J's time
and
.75(12) = 9 hrs is C's time
:
You can confirm this in the original equation, comes to slightly more than 1 because 2.77 is actually 2.76923 (36/13)