简算.0.56×0.125      24÷0.125       48×0.25       4÷0.25
3个回答

解题思路:0.56×0.125,根据积不变的性质,一个因数扩大几倍,另一个因数缩小相同的倍数.积不变.

24÷0.125,4÷0.25,根据商不变的性质简算.

48×0.25,把48拆分为:12×4,运用乘法结合律简算.

6.42×99,运用乘法分配律简算.

18.65-3.7+1.35-16.3,根据加、减法的运算性质简算.

(16.5×24+24×7.5)÷0.6,运用乘法分配律简算.

10.5×60×5×8,运用乘法交换律和结合律简算.

87.5×305-87.5-4×87.5,运用乘法分配律简算.

93÷0.31÷3,根据除法的运算性质简算.

15.8-4.72-6.28,根据减法的运算性质简算.

0.56×0.125

=(0.56÷8)×(0.125×8)

=0.07×1

=0.07;

24÷0.125

=(24×8)÷(0.125×8)

=192÷1

=192;

48×0.25=12×(4×0.25)

=12×1

=12;

4÷0.25

=(4×4)÷(0.25×4)

=16÷1

=16;

6.42×99

=6.42×(100-1)

=6.42×100-6.42

=642-6.42

=635.58;

18.65-3.7+1.35-16.3

=18.65+1.35-(3.7+16.3)

=20-20

=0;

(16.5×24+24×7.5)÷0.6

=(16.5+7.5)×24÷0.6

=24×24÷0.6

=576÷0.6

=960;

10.5×60×5×8

=(10.5×60)×(5×8)

=630×40

=25200;

87.5×305-87.5-4×87.5

=87.5×(305-1-4)

=87.5×300

=26250;

93÷0.31÷3

=93÷(0.31×3)

=93÷0.93

=100;

15.8-4.72-6.28

=15.8-(4.72+6.28)

=15.8-11

=4.8.

点评:

本题考点: 运算定律与简便运算.

考点点评: 此题考查的目的是理解掌握乘法的运算定律,加减法、乘法、除法的运算性质,并且能够灵活运用这些运算定律和运算性质进行简便计算.