一、口算。
7.6÷19 =
0.18 + 0.4 =
0.24 - 0.06 =
1.42×3 =
0.24÷6 =
3.72×0.2 =
1.23÷10 =
8.1 - 0.01 =
40÷800 =
0.9 + 1.2 =
1.7×40 =
114 - 99 =
2.8×600 =
3.5 + 5 =
57÷0.3 =
18÷8 =
6.6 - 0.82 =
2.6 + 8.4 =
32×0.08 =
4.8÷3 =
0.7×0.9 =
3.5 - 2.45 =
100×0.84 =
0.54÷2.7 =
0.84÷0.21 =
8.8 + 1.02 =
0.44×5 =
0.8 + 0.48 =
4.2÷70 =
3.6 - 0.9 =

0.4 0.58 0.18
4.26 0.04 0.744
0.123 8.09 0.05
2.1 68 15
1680 8.5 190
2.25 5.78 11
2.56 1.6 0.63
1.05 84 0.2
4 9.82 2.2
1.28 0.06 2.7

二、计算下面各题，怎样简便就怎样计算。
(1.35 + 0.75)÷(1.4×0.5)
(2.44 - 1.8)÷0.4×15
(9.3×2 + 9.3 + 9.3×5)×1.25

3 24 93