25 16吨
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米
分析:(1)先求出50比40多几,然后用多的数量除以40即可;
(2)把24吨看成单位“1”,要求的数是它的(1-
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),用乘法即可求出;
(3)把要求的数量看成单位“1”,10米是单位“1”的(1+20%),用除法求出单位“1”的量.
解答:(1)(50-40)÷40,
=10÷40,
=25%;
(2)24×(1-
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),
=24×
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,
=16(吨);
(3)10÷(1+20%),
=10÷1.2,
=
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(米);
故答案为:25,16吨,
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米.
点评:解答此题的关键是找出单位“1”的区别,求单位“1”的百分之几用乘法;已知单位“1”的百分之几是多少,求单位“1”用除法.