解题思路:(1)运用乘法分配律简算;
(2)运用加法交换了和结合律简算;
(3)先把64分解成4×2×8,再运用乘法结合律简算;
(4)先算除法,再算乘法,最后算减法;
(5)(6)根据除法的性质简算.
(1)49×102-2×49,
=49×(102-2),
=49×100,
=4900;
(2)15.63+2.54+4.37+7.46,
=(15.63+4.37)+(2.54+7.46),
=20+10,
=30;
(3)25×64×125,
=25×4×2×8×125,
=(25×4)×(8×125)×2,
=100×1000×2,
=100000×2,
=200000;
(4)560-912÷24×12,
=560-38×12,
=560-456,
=104;
(5)41000÷(41×5),
=41000÷41÷5,
=1000÷5,
=200;
(6)1736÷28+1064÷28,
=(1736+1064)÷28,
=2800÷28,
=100.
点评:
本题考点: 整数四则混合运算;运算定律与简便运算.
考点点评: 此题是考查四则混合运算,要仔细观察算式的特点,灵活运用一些定律进行简便计算.