一、口算。
5 - 1.2 =
9.9÷0.11 =
0.7×0.03 =
0.78÷0.3 =
0.25×400 =
7.26 + 0.86 =
3.07 - 1.23 =
13.8÷0.6 =
15×0.6 =
6.25×2 =
3.45 + 0.55 =
7.5 - 0.15 =
2.4÷0.04 =
10 - 4.3 =
1.5×0.03 =
0.25 + 3.45 =
7.8×0.4 =
2.7÷0.3 =
3×0.32 =
0.64÷0.16 =
7.9 + 5.4 =
0.63÷7 =
0.2×60 =
18.45÷9 =
0.72 + 0.6 =
0.62 - 0.43 =
0.42 + 3.5 =
1.25×800 =
0.58 + 0.77 =
0.4÷0.8 =

3.8 90 0.021
2.6 100 8.12
1.84 23 9
12.5 4 7.35
60 5.7 0.045
3.7 3.12 9
0.96 4 13.3
0.09 12 2.05
1.32 0.19 3.92
1000 1.35 0.5

二、解方程。
5.6x = 33.6
0.7x - 0.25x = 1.35
1.5×2 + 3x = 6.9

$x = 6$ $x = 3$
$x = 1.3$