解题思路:(1)先算乘法,再算加法;
(2)根据减法的性质简算;
(3)根据加法交换律和结合律简算;
(4)根据除法的性质简算;
(5)根据乘法分配律简算;
(6)根据商不变规律简算;
(7)先同时计算小括号里面的乘法和除法,再算括号外的除法;
(8)先算小括号的减法,再算中括号里面的乘法,然后算中括号里面的加法,最后算括号外的除法.
(1)320+80×15
=320+1200
=1520;
(2)18.62-3.44-8.52
=18.62-8.52-3.44
=10.1-3.44
=6.66;
(3)(5.2+8.35)+(4.8+1.65)
=(5.2+4.8)+(8.35+1.65)
=10+10
=20;
(4)72000÷(50×36)
=72000÷36÷50
=2000÷50
=40;
(5)99×0.625+0.625
=(99+1)×0.625
=100×0.625
=62.5;
(6)28000÷125
=(28000×8)÷(125×8)
=224000÷1000
=224;
(7)50.6-(1.8×10+15÷100)
=50.6-(18+0.15)
=50.6-18.15
=32.45;
(8)7332÷[68+(165-157)×11]
=7332÷[68+8×11]
=7332÷[68+88]
=7332÷156
=47.
点评:
本题考点: 整数四则混合运算;小数四则混合运算.
考点点评: 本题考查了四则混合运算,注意运算顺序和运算法则,灵活运用所学的运算定律进行简便计算.