一、口算。
$35+47=$
$65×3=$
$100-76=$
$369÷3=$
$4.33+5.42=$
$11×600=$
$2.8-0.28=$
$700÷14=$
$7.5-3.2=$
$1.6+0.8=$
$30×50=$
$860÷20=$
$70×22=$
$0.68-0.45=$
$360÷18=$
$25×36=$
$4×21=$
$92÷23=$
$4.45-2.4=$
$209×4=$
$616÷8=$
$221×30=$
$0.49+0.55=$
$105÷15=$

1.82
2.195
3.24
4.123
5.9.75
6.6600
7.2.52
8.50
9.4.3
10.2.4
11.1500
12.43
13.1540
14.0.23
15.20
16.900
17.84
18.4
19.2.05
20.836
21.77
22.6630
23.1.04
24.7

二、用竖式计算，带★的要验算。
$20.9 + 19.72 =$ $260 × 35 =$ ★$57.4 - 3.09 =$
$49 × 302 =$ $436 ÷ 56 =$ ★$80.65 + 6.301 =$

1.40.62
2.9100
3.54.31
4.14798
5.7……44
6.86.951