Question 1179693

Alex	25	minutes				
It does	  1/25	of the job in 1	hour			
Luke	35	minutes				
It does	  1/35	of thejob in 1	minutes			
Together they will do		   1/25 	+	   1/35 		
Together they will do		  5/73		of the job in one		minutes
So they will take		14  7/12	minutes