问题 解答题
用简便方法计算.
(1)56×
56
57

(2)3.3×
3
4
+0.75×5.7+75%
答案

(1)56×

56
57

=(57-1)×

56
57

=57×

56
57
-1×
56
57

=56-

56
57

=55

1
57

(2)3.3×

3
4
+0.75×5.7+75%,

=(3.3+5.7+1)×0.75,

=10×0.75,

=7.5.

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