Tina can do a job in 12 hrs
thus in 1 hr tina will do 1/12th job
in 8 hrs tina can do 1/12 * 8= 3/4
thus 1/4th job is remaining
ann can do a job in 9 hrs
thus
she can do 1/4th job in 9*1/4 = 2.25 hrs=2 hrs 15 min
thus in 1 hr tina will do 1/12th job
in 8 hrs tina can do 1/12 * 8= 3/4
thus 1/4th job is remaining
ann can do a job in 9 hrs
thus
she can do 1/4th job in 9*1/4 = 2.25 hrs=2 hrs 15 min