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1、比一比:抢答!,1.2+5=,6.2,1.25=,6,0.145=,0.7,1.254=,5,0.15100=,15,1.720=,34,0.1258=,1,0.152=,0.3,比一比:抢答!,0.123=,0.04,0.183=,0.06,0.2412=,0.02,12.33=,4.1,除数是整数的除法,算法和以前的除法一样,只不过是商的小数点要和被除数的小数点对齐。,除到被除数的末尾,还有余数时,一定要添0继续除。,当个位不够商1时,一定要商0占位。,猜一猜:哪些商小于1?,0.84271,76.5451,5.0461,1.21.21,=,规律:被除数=除数,则商=1;被除数除数,则商1
2、;被除数除数,则商1,填写下表,1500,3,3,商不变的规律:在除法里,被除数和除数同时扩大相同的倍数,商不变。,3,有132元,每人分给11元,,能够分给几个人?,有13.2元,每人分给1.1元,,能够分给几个人?,总结:小数除法很简单,除数看成整数算,被除数扩大同倍数,商永永远远不变。,猜一猜:除数、被除数看作多少计算最合适,4.681.5=()15,46.8,5.20.15=()15,520,2.40.15=()(),240,15,241.5=()(),240,15,0.241.5=()(),2.4,15,比一比:先看作多少计算,再计算,后验算,2.40.15=,241.5=,0.241.5=,0.240.15=,0.0240.15=,0.0240.015=,比一比:先看作多少计算,再计算,后验算,1.80.12=,181.2=,0.181.2=,0.180.12=,比一比:先看作多少计算,再计算,后验算,1.320.11=,1321.1=,0.1321.1=,0.1320.11=,