小学数学整数小数分数简便运算大全

小学数学整数小数分数简便运算大全


简介:
① 拆成a×(100+1) 84×101 =84×(100+1) =84×100+84×1 =8400+84 =8484 ② 拆成a×(100-1) 99×64 =(100-1)×64 =100×64-1×64 =6400-64 =6336 ③ a×(b+c)=a×b+a×c 99×13+13 =99×13+13×1 =13×(99+1) =13×100 =1300 ④ (a×b)×c=a×(b×c) 125×32×8 =125×8×32 =1000×32 =32000 ⑤a÷b÷c=a÷(b×c) 3600÷25÷4 =3600÷(25×4) =3600÷100 =36 ⑥ (a+b)+c=a+(b+c) 278+463+22+37 =(278+22)+(463+37) =300+500 =800 ⑦ a-b-c=a-(b+c) 214-(85+14) =214-14-85 =200-85 =115 ⑧ (a-b)×c=a×c-b×c 178×101-178 =178×(101-1) =178×100 =17800