Note that "t divided by 5/12" is the same as "t multiplied by 12/5." Thus,
12t -3
----- = ----------
5 10
Mult. the numerator and denom. of the 1st fraction by 2 results in:
-24t = -3
Dividing both sides by -24 gives us a the value for t:
-24t = -3
------ = ------ = t = 1/8
-24 -24
The solution is t = 1/8.