解题思路:(1)利用加法交换律与结合律简算;
(2)(3)(4)(5)利用乘法分配律简算.
(1)[5/8]+[11/12]+[3/8]+[1/12]
=[5/8]+[3/8]+([1/12]+[11/12])
=1+1
=2;
(2)([1/3]+[1/4]+[1/6])×24
=[1/3]×24+[1/4]×24+[1/6]×24
=8+6+4
=18;
(3)[7/8]×7+[7/8]
=[7/8]×(7+1)
=[7/8]×8
=7;
(4)(12+[6/13])×[13/12]
=12×[13/12]+[6/13]×[13/12]
=13+[1/2]
=13[1/2];
(5)62.5×[1/5]+[4/5]×62.5-62.5
=62.5×([1/5]+[4/5]-1)
=0.
点评:
本题考点: 分数的四则混合运算;运算定律与简便运算.
考点点评: 此题考查分数的简便运算,根据数字与符号特点灵活选用运算定律简算.