[0.8+0.75×(0.65-0.25)]÷0.01
455×7.6+112÷
+43.3×76
+
+
+…+
解:(1)2506-10517÷13+14×106,=2506-809+1484,
=1697+1484,
=3181;
(2)[0.8+0.75×(0.65-0.25)]÷0.01,
=[0.8+0.75×0.4]÷0.01,
=[0.8+0.3]÷0.01,
=1.1÷0.01,
=110;
(3)455×7.6+112÷
+43.3×76,=455×7.6+112×7.6+433×7.6,
=(455+112+433)×7.6,
=1000×7.6,
=7600;
(4)
+
+
+…+
,=1+2×(
-
+
-
+
+…+
-
),=1+2×(

),=1+
,=
.分析:(1)、(2)按照先算乘除,再算加减,有括号的先算括号里面的运算顺序计算;
(3)用乘法分配律简算;
(4)因为:(1+2+…+n)=n(n+1)÷2,那么:
=
=2(
-
),由此求解.点评:第(4)题较复杂,先找出规律,再根据规律化简求解.