1:4 9:2 5:2 2:3 0.25
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2.3
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分析:(1)根據(jù)比的基本性質(zhì)作答,即比的前項和后項同時乘或除以一個數(shù)(0除外)比值不變;
(2)用比的前項除以后項即可.
解答:(1)25:100,
=(25÷25):(100÷25),
=1:4;
25:100,
=25÷100,
=0.25,
(2)
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:
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,
=(
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×
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):(
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×
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),
=9:2,
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:
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,
=
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÷
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,
=
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,
(3)0.9:0.36,
=(0.9×100):(0.36×100),
=90:36,
=(90÷18):(36÷18),
=5:2,
0.9:0.36,
=0.9÷0.36,
=2.5;
(4)
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噸:375千克,
=250千克:375千克,
=250:375,
=(250÷125):(375÷125),
=2:3,
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噸:375千克,
=250千克:375千克,
=250:375,
=250÷375,
=
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.
比 | 25:100 | : | 0.9:0.36 | 噸:375千克 |
最簡整數(shù)比 | 1:4 | 9:2 | 5:2 | 2:3 |
比值 | 0.25 |  | 2.5 |  |
點評:注意化簡比的結(jié)果是一個比,它的前項和后項都是整數(shù),并且是互質(zhì)數(shù);而求比值的結(jié)果是一個商,可以是整數(shù),小數(shù)或分數(shù).