1. 直接写得数。
①$8.53 - 1.53 =$
②$7.7 - 3.9 =$
③$12.3 + 5.8 =$
④$6.9 - 5.7 =$
⑤$2.4 + 1.8 =$
⑥$13.4 - 6.3 =$
⑦$10 - 3.62 =$
⑧$4.2 + 1.8 =$
⑨$3.7 + 7.7 =$
⑩$1.8 + 3.2 =$
⑪$8.61 - 4.6 =$
⑫$6.72 + 2.9 =$
⑬$6.2 - 3.6 =$
⑭$3.12 + 2.83 =$
⑮$3.36 + 4.64 =$
⑯$8.59 - 2.4 =$
⑰$9.62 - 4.02 =$
⑱$3.54 - 3.45 =$
⑲$6.21 + 7.78 =$
⑳$8.91 + 6.44 =$
㉑$6.88 + 7.12 =$
㉒$3.3 - 1.4 =$
㉓$2.74 - 0.74 =$
㉔$9.3 + 7.98 =$
㉕$5.7 + 6.3 + 2.53 =$
㉖$5.2 + 8.78 - 3.58 =$
㉗$8.56 - 1.43 - 2.1 =$
㉘$6.4 + 5.18 + 3.2 =$
㉙$4.37 - 1.1 - 2.27 =$
㉚$5.6 - 0.24 + 3.74 =$
㉛$2.89 + 1.6 - 2.49 =$
㉜$6.69 + 3.3 - 1.99 =$
㉝$9.8 - 2.5 + 3.46 =$
㉞$5.72 + 1.28 + 2.6 =$
㉟$3.45 - 0.55 - 0.9 =$
㊱$10.5 + 1.2 + 3.17 =$

①$8.53 - 1.53 = 7$
②$7.7 - 3.9 = 3.8$
③$12.3 + 5.8 = 18.1$
④$6.9 - 5.7 = 1.2$
⑤$2.4 + 1.8 = 4.2$
⑥$13.4 - 6.3 = 7.1$
⑦$10 - 3.62 = 6.38$
⑧$4.2 + 1.8 = 6$
⑨$3.7 + 7.7 = 11.4$
⑩$1.8 + 3.2 = 5$
⑪$8.61 - 4.6 = 4.01$
⑫$6.72 + 2.9 = 9.62$
⑬$6.2 - 3.6 = 2.6$
⑭$3.12 + 2.83 = 5.95$
⑮$3.36 + 4.64 = 8$
⑯$8.59 - 2.4 = 6.19$
⑰$9.62 - 4.02 = 5.6$
⑱$3.54 - 3.45 = 0.09$
⑲$6.21 + 7.78 = 13.99$
⑳$8.91 + 6.44 = 15.35$
㉑$6.88 + 7.12 = 14$
㉒$3.3 - 1.4 = 1.9$
㉓$2.74 - 0.74 = 2$
㉔$9.3 + 7.98 = 17.28$
㉕$5.7 + 6.3 + 2.53 = 14.53$
㉖$5.2 + 8.78 - 3.58 = 10.4$
㉗$8.56 - 1.43 - 2.1 = 5.03$
㉘$6.4 + 5.18 + 3.2 = 14.78$
㉙$4.37 - 1.1 - 2.27 = 1$
㉚$5.6 - 0.24 + 3.74 = 9.1$
㉛$2.89 + 1.6 - 2.49 = 2$
㉜$6.69 + 3.3 - 1.99 = 8$
㉝$9.8 - 2.5 + 3.46 = 10.76$
㉞$5.72 + 1.28 + 2.6 = 9.6$
㉟$3.45 - 0.55 - 0.9 = 2$
㊱$10.5 + 1.2 + 3.17 = 14.87$

2. 计算下面各题,能简算的要简算。
①$67.7 - 5.34 - 6.26$
②$9.4 - 1.5 - 2.5$
③$5.31 + 1.28 + 5.16$
④$7.82 + 3.6 - 1.79$
⑤$6.75 - 3.53 + 9.53$
⑥$22.56 - (2.56 + 7.5)$

①
$67.7 - 5.34 - 6.26$
$=67.7-(5.34+6.26)$
$=67.7-11.6$
$=56.1$
②
$9.4 - 1.5 - 2.5$
$=9.4-(1.5+2.5)$
$=9.4-4$
$=5.4$
③
$5.31 + 1.28 + 5.16$
$=6.59+5.16$
$=11.75$
④
$7.82 + 3.6 - 1.79$
$=11.42-1.79$
$=9.63$
⑤
$6.75 - 3.53 + 9.53$
$=6.75+(9.53-3.53)$
$=6.75+6$
$=12.75$
⑥
$22.56 - (2.56 + 7.5)$
$=22.56-2.56-7.5$
$=20-7.5$
$=12.5$