A computer expert can do a job in 6 hours. His secretary can do the same job in 7hrs. After the expert works on the job foe 2 hours, his secretary takes it and complete the job. How many hrs did it take her to complete the job?
after 2hrs the experthad completed 1/3 of the job...what do I have to do now?? 1/3 * 1/7
..I'm not sure...Could someone help me??? Please.