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用简便方法计算:(1)(0.2)2008×(-25)1005;(2)19962-16.

题目详情
用简便方法计算:
(1)(0.2)2008×(-25)1005
(2)19962-16.
▼优质解答
答案和解析
(1)(0.2)2008×(-25)1005
=(0.2)2008×(-52010),
=(0.2)2008×(-52008)×52
=-(0.2×5)2008×25,
=-25;

(2)19962-16,
=19962-42
=(1996+4)(1996-4),
=2000×1992,
=3984000.