139x137/138+137x1又1/138
=（138+1）×137/138+137+137/138
=137+137/138+137+137/138
=274+137/69
=274+1又68/69
=275又68/69
139x137/138+137x1又1/138的简便运算 答案上是275又68/69
139x137/138+137x1又1/138
=（138+1）×137/138+137+137/138
=137+137/138+137+137/138
=274+137/69
=274+1又68/69
=275又68/69