<span>(12 1/2)/(2 1/2) = (16 2/3)
</span><span>12 1/2 * у = 2 1/2 * 16 2/3 свойство пропорции
</span><span>12 1/2 * у = 5/2 * 50/3
</span><span>12 1/2 * у = 250/6
</span><span>у = 250/6 : 12 1/2 = 250/6 : 25/2
</span><span>у = 250/6 * 2/25
</span><span>у = 10/3
</span><span>у = 3 1/3
</span><span>Проверка: 12 1/2 : 2 1/2 = 16 2/3 : 3 1/3
</span><span>25/2 * 2/5 = 50/3 * 3/10
</span><span>25/5 = 50/10
</span><span> 5 = 5
</span><span>Ответ: у = 3 1/3. </span>
210:10=21 см........................
3416/8
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32
21
16
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56