1. 直接写出得数。
$0 + 10.02 =$ $18 - 15.46 =$ $1.5 + 0.9 - 1.5 + 0.9 =$
$1.6 + 4.8 =$ $78 - 0.8 =$ $20 - 15.8 - 4.2 =$
$1.2 + 3.4 =$ $9.1 - 4.9 =$ $7.85 + 2.5 + 0.15 + 6.5 =$
$3.2 + 1.7 =$ $5.4 - 1.7 =$ $1.4 - 0.5 =$
$5.6 + 3.4 =$ $0.43 - 0.3 =$ $0.45 + 0.55 =$
$9.7 - 6.7 =$ $4.82 - 1.62 =$ $0.09 + 1.26 =$

0 + 10.02 = 10.02
18 - 15.46 = 2.54
1.5 + 0.9 - 1.5 + 0.9 = 1.8
1.6 + 4.8 = 6.4
78 - 0.8 = 77.2
20 - 15.8 - 4.2 = 0
1.2 + 3.4 = 4.6
9.1 - 4.9 = 4.2
7.85 + 2.5 + 0.15 + 6.5 = 17
3.2 + 1.7 = 4.9
5.4 - 1.7 = 3.7
1.4 - 0.5 = 0.9
5.6 + 3.4 = 9
0.43 - 0.3 = 0.13
0.45 + 0.55 = 1
9.7 - 6.7 = 3
4.82 - 1.62 = 3.2
0.09 + 1.26 = 1.35

2. 计算下列各题，能简算的要简算。
$39.6 + 5.63 - 28.75$ $15.14 - (10.28 - 0.86)$
$70.9 - 1.25 - 1.75$ $3.73 + 1.25 + 5.27 + 8.75$

$39.6 + 5.63 - 28.75$
$=45.23 - 28.75$
$=16.48$
$15.14 - (10.28 - 0.86)$
$=15.14 - 10.28 + 0.86$
$=15.14 + 0.86 - 10.28$
$=16 - 10.28$
$=5.72$
$70.9 - 1.25 - 1.75$
$=70.9 - (1.25 + 1.75)$
$=70.9 - 3$
$=67.9$
$3.73 + 1.25 + 5.27 + 8.75$
$=(3.73 + 5.27) + (1.25 + 8.75)$
$=9 + 10$
$=19$

3. 列竖式计算。
$8.94 + 3.26 =$ $5.8 + 3.24 =$ $11 - 7.25 =$
$14.26 - 10.19 =$ $20.31 - 12.82 =$ $18.27 + 11.73 =$

8.94
+ 3.26
------
12.20
$8.94 + 3.26 = 12.2$
5.80
+ 3.24
------
9.04
$5.8 + 3.24 = 9.04$
11.00
7.25
-------
3.75
$11 - 7.25 = 3.75$
14.26
-10.19
-------
4.07
$14.26 - 10.19 = 4.07$
20.31
-12.82
-------
7.49
$20.31 - 12.82 = 7.49$
18.27
+11.73
-------
30.00
$18.27 + 11.73 = 30$