Question

John is jogging along a track. He has already jogged 5 2/3 km. How many more kilometres does he have to jog to complete the track of 9 1/4

Answer 1

9 1/4 - 5 2/3

well what is a least common multiple of 4 and 3
I pick 12
so
9 3/12 - 5 8/12
well that is inconvenient. 8 is bigger than 3
so add 12/12 to 3/12 and subtract 1 from 9
8 15/12 - 5 8/12
3 7/12
not much more we can do to that