2 11/78 you just have to simply multiply 64/143 x2 because since it can't be subtracted. And after you multiply 64/143, you just have to subtract normally which is 128-21 and 286-208. Then since your answer came out to an improper fraction, so you have to simplify by dividing 107 divided by 78. Then you will get your answer which is 2 11/78.
