ʱ : һ 人教版四年级数学下学期期末总复习资?- 百度文库ϿʼĶ
˽̰꼶ѧѧĩܸϰ
Ķ˽̰꼶ѧѧĩܸϰռ!վΪṩľƷѧԴ!˽̰꼶ѧѧĩܸϰһ㣺
*1 ˳
1ûŵʽֻмӼֻг˳ҪҰ˳Σ㡣
2ûŵʽмӼг˳Ҫ˳Ӽ
3ʽʱҪġ *2 ӷ˷ͳͳΪ㡣 *3 й0㣺 1һ0ԭ 2κһ00
300һ00 00ò̶;50ò. ) λ뷽
1ݷ;ȷľص㡣ߡǵĻͶ
2λüԡλùϵ(۲ȷ)
1 ҳ
3·ͼĻơ )㶨ɼ㣺
1ӷ㶨ɣ1ӷɣӣλãͲ䡣 a+b=b+a
2ӷɣӣȰǰӣټϵȰѺӣټϵһͲ䡣a+b+c=a+(b+c)
ӷһʹá
磺++++ʲô 2ʣһȥȥĺ͡ a-b-c=a-(b+c)
3˷㶨ɣ1˷ɣˣλã䡣 a b = b a
2˷ɣˣȰǰˣٳԵҲȰѺˣٳԵһ䡣
a b c = a ( b c )
˷һʹá 磺ļ
2 ҳ
3˷ɣĺһˣȰֱˣٰѻӡa+bc=ac+bc 4ʣһڳĻ
a b c = a ( b c) 5йؼչ
.+. .. 3796+373+37 ״0.6+0.4-0.6+0.4 3899+99 ģ Сʣ
1ĸ101001000ķСʾ 2СʮƷһֱʽ
3Сļλʮ֮һٷ֮һǧ֮һֱд0.10.010.001
4ÿλĽ10
5СĶдְСҪ˳ζÿһ
дְдд0д0Сдÿһ
СʣСĩβ0ȥ0СĴС䡣ע⣺См0ȥȡʱһЩĩβ0ȥÿԻСȡ
3 ҳ
ССȽϣȱȽ֣ͬȽʮλʮλͬȽϰٷλ
СλƶСС仯ɣ СңƶһλСԭ10 ƶλСԭ100 ƶλСԭ1000
Ķ˽̰꼶ѧѧĩܸϰռ!վΪṩľƷѧԴ!˽̰꼶ѧѧĩܸϰ
СƶһλСС10ССΪԭ
ƶλСС100ССΪԭ ƶλСС1000ССΪԭ ĸд130ǧˣ800ˣ ȵλǧ
λƽǧƽƽƽ λǧ˿
10СĽ룩λС뾫ȷٷλᷨ
ʾȷλһλСʾȷʮλλСʾȷٷλȡʱСĩβ0ȥ
4 ҳ