最小的质数与最小的合数的和的倒数是 .
写出下列各数的相邻整十数。( ),789,( ) ( ),455,( )( ),320,( ) ( ),309,( )
写出下列各数的相邻整十数。( ),210,( ) ( ),900,( )( ),315,( ) ( ),426,( )
写出下列各数的相邻整十数。( ),390,( ) ( ),345,( )( ),310,( ) ( ),400,( )
写出下列各数相邻的数。( ),245,( ) ( ),345,( )( ),311,( ) ( ),756,( )
写出下列各数相邻的数。( ),324,( ) ( ),899,( )( ),598,( ) ( ),477,( )