①x-3.4=2.42
②12.8÷x=1.6
③9x-7x=3.8
④23.6-x=9.15
⑤1+0.25x=1.68
⑥0.3x+4×0.8=3.83
40×25%= 1.03×10= 3×45= 1÷10%= 2.8×=
1.57﹣0.85= 0.49÷0.7= 3.05+6.2= 0.6:0.75= kg:40g=