一、口算。
89÷0.89 =
6.8 + 0.22 =
5 - 1.28 - 2.72 =
3.4×0.4 =
2 - 0.66 =
3.52×49 + 3.52 =
10 - 0.05 =
3.2÷80 =
(1.6 + 0.5)÷10 =
2.4÷0.04 =
3.52×0.2 =
0.7×(1 - 0.6) =
2.1 + 6.9 =
1.26 - 0.9 =
0.1 - 0.3×0.1 =
6.4÷4 =
1.05 + 3.3 =
10×(0.6÷0.06) =
7.32×10 =
9÷4.5 =
(4 - 0.4)×2.5 =
2.2 + 6.8 =
2.5×200 =
9÷5 + 1÷5 =
4.5÷0.6 =
1.7 - 0.45 =
1.25×8 + 3.2 =
0.8×1.25 =
0.068 + 0.32 =
0.48÷0.5×100 =

100 7.02 1
1.36 1.34 176
9.95 0.04 0.21
60 0.704 0.28
9 0.36 0.07
1.6 4.35 100
73.2 2 9
9 500 2
7.5 1.25 13.2
1 0.388 96

二、解方程。
3.6x - 50×0.2 = 26
1.8÷0.9 + 3x = 8.6
5x - 1.2×3.5 = 6

$x = 10$ $x = 2.2$
$x = 2.04$