解题思路:(1)先算加法,再算中括号里面的乘法,再算减法,最后算括号外面的乘法;
(2)根据除法的性质进行简算;
(3)根据乘法分配律进行简算;
(4)根据乘法分配律进行简算;
(5)按照从左向右的顺序进行计算;
(6)先算加法,再算乘法,再算减法,最后算除法.
(1)[800×(1+[1/4])-360]×2.5
=[800×1[1/4]-360]×2.5
=[1000-360]×2.5
=640×2.5
=1600;
(2)7200÷25÷4
=7200÷(25×4)
=7200÷100
=72;
(3)46.5×43.5+4.35×285-25×43.5
=46.5×43.5+43.5×28.5-25×43.5
=(46.5+28.5-25)×43.5
=50×43.5
=2175;
(4)5.25×[11/12]+[11/12]×[3/4]
=(5.25+[3/4])×[11/12]
=6×[11/12]
=[11/2];
(5)[5/6]×[1/15]÷[7/18]
=[1/18]÷[7/18]
=[1/7];
(6)[3.75-(0.2+[1/3])×4.5]÷13.5
=[3.75-[8/15]×4.5]÷13.5
=[3.75-2.4]÷13.5
=1.35÷13.5
=0.1.
点评:
本题考点: 整数、分数、小数、百分数四则混合运算;运算定律与简便运算.
考点点评: 考查了运算定律与简便运算,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简便计算.