问题
解答题
用递等式计算,怎样简便就怎样算 (1)3.7-2.2+7.3-7.8 (2)375+450÷18×25 (3)2.9×
(4)
|
答案
(1)3.7-2.2+7.3-7.8,
=(3.7+7.3)-(2.2+7.8),
=11-10,
=1;
(2)375+450÷18×25
=375+25×25
=375+625
=1000;
(3)2.9×
+1.1×1 8
,1 8
=(2.9+1.1)×
,1 8
=4×
,1 8
=
;1 2
(4)
÷(1 4
-3 4
),1 2
=
÷1 4
,1 4
=1.