作业帮①3/4*2/7+5/7÷3/4 ②68/69*69
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/03 01:09:29
①3/4*2/7+5/7÷3/4 ②68/69*69
①3/4*2/7+5/7÷3/4 ②68/69*69
①3/4*2/7+5/7÷3/4 ②68/69*69
①3/4*2/7+5/7÷3/4
=3/4*2/7+5/7*4/3
=3/4*2/7+2/7*10/3
=（3/4+10/3）*2/7
= 49/12*2/7
=7/6
②68/69*69
=68*69/69
=68