272×271分之37 27×26分之21 45乘46分之27 99乘7分之3＋7分之3 简便计算

272×271分之37
=(271+1)*37/271
=37+37/271
=37又37/271
99乘7分之3＋7分之3
=（99+1）*3/7
=100*3/7
=300/7
27×26分之21
=(26+1)*21/26
=21+21/26
=21又21/26
45乘46分之27
=(64-1)*27/46
=27-27/46
=26又19/46