怎样简便就怎样算．（1）×2+2×（2）101×0.48（3）7.28﹣（1.25+0.28）（4）19.9+19.9×99．
口算．+=﹣=+=﹣=+=+=﹣= 2﹣= 1﹣﹣=
直接写出得数．﹣=+=+=+= 1﹣=﹣= 3+=﹣= 3﹣1=+=+=+3=
．
直接写出得数．﹣= 0.7﹣0.62= 12÷25== 10=+×0= 13×= 10=
直接写得数．+=+= 1﹣=﹣=﹣=+=﹣1=﹣= 3﹣1=+=
×2
+2
+
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﹣
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﹣
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+
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= 1﹣
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﹣
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+
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= 3+
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﹣
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+
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．
﹣
= 0.7﹣0.62= 12÷25=
=
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×0= 13
×
= 10
=
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= 1﹣
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﹣
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﹣1=
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