Working, independently Gilligan takes 12 hours to finish a certain work. He finishes 2/3 of the work. The rest of the work is finished by Skipper whose rate is 1/10 of Gilligan. In how much time does Skipper finish his work?

My Effort:

Gilligan takes 12 hours to complete the job. This tells me that he does (1/12) of the job per hour.

Gilligan finishes 2/3 of the job. This tells me that 1/3 of the job remains to be done.

Skipper completes the rest of Gilligan's work. This tell me that Skipper completes (1/10)(1/12) or 1/120 of the rest of the work.

Is this right? If it is right, I did it without algebra. However, I would like to know if there is an equation set for this problem.