2÷[(127-136)×9]×61.25×67.875+0.125×6787.5+125×0.53375.

问题描述:

2÷[(

1
27
-
1
36
)×9]×6
1.25×67.875+0.125×6787.5+125×0.53375.

(1)2÷[(

1
27
-
1
36
)×9]×6,
=2÷[
1
27
×9-
1
36
×9]×6,
=2÷[
1
3
-
1
4
]×6,
=2÷
1
12
×6,
=2×12×6,
=144;
(2)1.25×67.875+0.125×6787.5+125×0.53375,
=125×0.67875+125×6.7875+125×0.53375,
=125×(0.67875+6.7875+0.53375),
=125×8,
=1000.
答案解析:(1)中括号内运用乘法分配律简算,然后再算括号外的除法和乘法;
(2)根据数字特点,原式变为125×0.67875+125×6.7875+125×0.53375,运用乘法分配律简算.
考试点:整数、分数、小数、百分数四则混合运算;运算定律与简便运算.
知识点: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律简便计算.