)( )( )( )( )( 19 )( ) (13 ) ( )
)( )( )( )( )( 19 )( ) (13 ) ( )
(13-19题)
找规律19()13()7()0
-7×(-19分之4)+13×(-19分之4)-6×(-19分之4);
(-11)+(-12)+(-13)+(-14)+.+(-19)
11,13,17,19,23 )
3.15,16,13,19,11,22,( ),( ),7,( ),...
找规律 1,7,13,19,( ),( ).
找规律7,9,13,19,27,37,(),(),(),()
1/(12×13)+1/(13×14)+……+1/(19×20)等于多少
1.(1/12*13)+(1/13+14)+.+(1/19+20)的值
4.9.9.15.14()19()()