已知a>b>c,a、b和c三个数的平均数是1.8,则b一定大于1.8. .(判断对错)
× = ×= × =1.
任何一个数(零除外)与它的倒数的乘积是1. .
和 互为倒数.
× =× =× =9× =1.
35× =0.5× =× =6÷ =1.