÷ × ÷ × ÷
×3= × = 4.2× = ×3= 3.3× = × =
÷ = ÷ = 0÷ = 1÷ = ÷ = ÷0.25=
① × ÷
②2.4÷ +6.4
③ + ÷
④( + )×12
⑤( - )÷( + )
⑥ × + ÷