To add the fractions we need to find the lowest common denominator. Since 5 and 12 have no factors in common the LCD is 5*12=60. We then convert each fraction into the right number of sixtieths. 1/5 is 12/60 and 5/12 is 5*5/60=25/60. Adding together two like quantities is easy, like adding apples, where our apples are sixtieths. So 12+25 sixtieths is 37/60.