一、口算。
2.7×50 =
2.5 + 0.54 =
0.8÷0.16 =
7.01 - 0.71 =
0.63÷0.9 =
3.1×0.4 =
1.44÷0.6 =
0.19×20 =
0.19 + 1.9 =
0.3×4.2 =
0.65÷0.13 =
4.16 - 2.08 =
4.2 - 1.9 =
1.26 + 7.6 =
0.56×0.5 =
3.2×100 =
3.4 - 0.52 =
5.6÷0.08 =
3.02 + 3.68 =
12÷0.25 =
2.6 + 1.72 =
16.8÷0.8 =
7.13 - 6.1 =
8÷0.5 =
7.2 - 2.8 =
0.08×15 =
0.26 + 0.4 =
2.7×0.2 =
1÷0.4 =
2 - 0.35 =

135 3.04 5
6.3 0.7 1.24
2.4 3.8 2.09
1.26 5 2.08
2.3 8.86 0.28
320 2.88 70
6.7 48 4.32
21 1.03 16
4.4 1.2 0.66
0.54 2.5 1.65

二、解方程。
x - 9.4 = 3.6
4x÷6 = 1.8
0.19x + 5.6 = 9.4

$x = 13$ $x = 2.7$
$x = 20$