问题
解答题
用简便方法计算.
(1)44.4×25
(2)0.64×125.
答案
(1)44.4×25,
=(40+4+0.4)×25,
=40×25+4×25+0.4)×25,
=1000+100+10,
=1110;
(2)0.64×125,
=0.8×0.8×125,
=0.8×(0.8×125),
=0.8×100,
=80.
用简便方法计算.
(1)44.4×25
(2)0.64×125.
(1)44.4×25,
=(40+4+0.4)×25,
=40×25+4×25+0.4)×25,
=1000+100+10,
=1110;
(2)0.64×125,
=0.8×0.8×125,
=0.8×(0.8×125),
=0.8×100,
=80.