10:x=5
x=10:5
x=2
a2=10
a=10:2
a=5
a:2=5
a=5*2
a=10
1)60-6=55(км.)-скорость течения.
Это только первое действие.Остальные нк знаю.Прости(
<span><span><span><span>
а
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100
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1000
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100000
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а*10
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а:10
</span><span><span> 1</span></span><span>
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