計(jì)算,能簡(jiǎn)便盡量簡(jiǎn)便計(jì)算.
(1)2000-586-114
(2)67×101-67
(3)125×48
(4)34×126+37×73+37
(5)[(180-159)×12]÷3.
解:(1)2000-586-114
=2000-(586+114),
=2000-700,
=1300;
(2)67×101-67
=(101-1)×67,
=100×67,
=6700;
(3)125×48
=125×8×6,
=1000×6,
=6000;
(4)34×126+37×73+37
=4284+2701+37,
=7022;
(5)[(180-159)×12]÷3
=[21×12]÷3,
=84.
分析:算式(1)可根據(jù)一個(gè)數(shù)減兩個(gè)數(shù),等于減去這兩個(gè)數(shù)的和的減法性質(zhì)進(jìn)行計(jì)算;
算式(2)可根據(jù)乘法分配律計(jì)算;
算式(3)可將48變?yōu)?×6后進(jìn)行計(jì)算;
算式(4)、(5)根據(jù)四則混合運(yùn)算的運(yùn)算順序計(jì)算即可.
點(diǎn)評(píng):完成算式(4)時(shí)要注意本題不適用于乘法分配律.