1) 2 13/48 + 2 5/12=109/48 + 29/12=109/48 + 116/48=225/48
2)225/48 : 3 3/4=225/48 * 4/15=15/12
3)9 3/4 : 12=39/4 * 1/12=39/48
4)15/12-39/48=60/48-39/48=21/48=7/16
