考点:整数四则混合运算,运算定律与简便运算
专题:运算顺序及法则,运算定律及简算
分析:(1)(6)(7)(9)(12)利用乘法分配律简算;
(2)利用减法的性质简算;
(3)把88=8×11计算;
(4)利用乘法交换律简算;
(5)(10)利用加法交换律与结合律简算;
(8)把44=4×11计算;
(11)利用除法的性质简算.
解答:
解:(1)125×103-125×3
=125×(103-3)
=125×100
=12500;
(2)2700-425-175
=2700-(425+175)
=2700-600
=2100;
(3)125×88
=125×8×11
=1000×11
=11000;
(4)25×7×4
=25×4×7
=100×7
=700;
(5)32+26+74+168
=32+168+(26+74)
=200+100
=300;
(6)63×25+25×37
=(63+37)×25
=100×25
=2500;
(7)99×32+32
=(99+1)×32
=100×32
=3200;
(8)25×44
=25×4×11
=100×11
=1100;
(9)48×213-13×48
=48×(213-13)
=48×200
=9600;
(10)41+127+59+173
=41+59+(173+127)
=100+300
=400;
(11)1300÷25÷4
=1300÷(25×4)
=1300÷100
=13;
(12)156×l0l-156
=156×(l0l-1)
=156×l00
=15600.
点评:整数混合运算,抓住数字和运算符号的特点,灵活选用适当的方法和运算定律简算.