问题
解答题
计算.能简算的要简算,并写出简算过程. (1)(0.12+0.22+0.32+0.42)2÷(0.13+0.23+0.33+0.43) (2)3.97÷7+
(3)0.0021×[1
(4)0.125×0.25×0.5×64 (5)4936×(0.75×42.7-0.573×25+57.3)÷3. |
答案
(1)(0.12+0.22+0.32+0.42)2÷(0.13+0.23+0.33+0.43),
=(0.01+0.04+0.09+0.16)2÷(0.001+0.008+0.027+0.064),
=0.32÷0.1,
=0.09÷0.1,
=0.9;
(2)3.97÷7+
×4.03-1 7
,1 7
=3.97×
+1 7
×4.03-1 7
,1 7
=(3.97+4.03-1)×
,1 7
=7×
,1 7
=1;
(3)0.0021×[1
+2.93÷(116 7
-1.9)]÷0.001,2 3
=0.0021×[1
+26 7
÷993 100
]÷0.001,23 30
=0.0021×[1
+6 7
×293 100
]÷0.001,30 293
=0.0021×[1
+6 7
]÷0.001,3 10
=0.0021×
÷0.001,151 70
=0.00453÷0.001,
=4.53;
(4)0.125×0.25×0.5×64,
=0.125×0.25×0.5×8×4×2,
=(0.125×8)×(0.25×4)×(0.5×2),
=1×1×1,
=1;
(5)4936×(0.75×42.7-0.573×25+57.3)÷3.
=4936×(32.025-14.325+57.3)÷3,
=4936×75÷3,
=370200÷3,
=123400.