So we want to know the difference between a= 126 1/4 and b= 78 2/3. Lets turn them into a fraction: a = 124*4 + 1/4 = 496/4 + 1/4 = 495/4. b= 78*3 + 2/3 = 234/3 + 2/3 = 236/3. Now we find the common denominator of a and b: and that is 12. so lets multiply a by 3/3 and b by 4/4: (495/4)*(3/3)=1485/12. (236/3)*(4/4)=944/12. Now the difference is: 1485/12 - 944/12=541/12 and that is: 45 1/12
