512×[(1−58)×56]19(2+0.5)×1.2−0.6÷275371×539+248000×0.371+2130×37.140.2×8.1×45÷(0.8×81×20.1)1990×1999-1989×2000363+411×362363×411−48.
×[(1−)×]
(2+0.5)×1.2−0.6÷
371×539+248000×0.371+2130×37.1
40.2×8.1×÷(0.8×81×20.1)
1990×1999-1989×2000
.
答案和解析
(1)
×[(1-)×]
=×[×],
=××,
=;
(2)×(2+0.5)×1.2-0.6÷,
=××-×,
=-,
=;
(3)371×539+248000×0.371+2130×37.1,
=371×539+248×371+213×371,
=(539+248+213)×371,
=1000×371,
=371000;
(4)40.2×8.1×÷(0.8×81×20.1)
=40.2×8.1×0.8÷0.8÷81÷20.1,,
=(40.2÷20.1)×(8.1÷81)×(0.8÷0.8),
=2×0.1×1,
=0.2;
(5)1990×1999-1989×2000,
=1990×(2000-1)-1989×2000,
=1990×2000-1990-1989×2000,
=2000×(1990-1989)-1990,
=2000-1990,
=10;
(6).
=363+411×(363−1) |
363×411−48 |
,
=363+411×363−411 |
363×411−48 |
=,
=1.
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