6×57×4 7+77×7 5×54×6
6×77×6 6×97×8 6×98×6
8.9+3.01= 1- + = 1.2×5= 3.8÷0.038=
÷ = 3604÷62≈ 0.62-0.32= 1÷10%=
( - )×24= ×8÷ ×8=