A special balloon increases by two-fifths of its previous volume every hour when placed under water. If its original volume is 500cm³, what will its volume be after 2 hours underwater?
Як балони махсус ҳар соат, вақте ки он дар зери об гузошта мешавад, ба ду панҷум аз ҳаҷми қаблии худ меафзояд. Агар ҳаҷми аслии он 500 см³ бошад, пас пас аз 2 соат дар зери об ҳаҷми он чӣ гуна хоҳад буд?
How much does the balloon increase in the first hour? ** In the first hour, the balloon will increase in volume by two-fifths of 500cm³ which is (2/5)*500cm³ = <<2/5*500=200>>200cm³
What will the balloon's volume be after the first hour? ** After the first hour, it will have a volume of (500+200)cm³ = <<(500+200)=700>>700cm³
How much does the balloon increase in the second hour? ** In the second hour, it will increase in volume by two-fifths of 700cm³ which is (2/5)*700cm³ = <<2/5*700=280>>280cm³
What will the balloon's volume be after the second hour? ** After the second hour, it's volume will be (700+280)cm³ = <<(700+280)=980>>980cm³
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How much does the balloon increase in the first hour? ** Дар соати аввал, баллон ҳаҷмро бо ду панҷум аз 500cm³ зиёд мекунад, ки ин (2/5)*500cm³ = <<2/5*500=200>>200cm³ мебошад.  
What will the balloon's volume be after the first hour? ** Пас аз соати аввал, ҳаҷми он (500+200)cm³ = <<(500+200)=700>>700cm³ хоҳад буд.  
How much does the balloon increase in the second hour? ** Дар соати дуюм, он ҳаҷмро бо ду панҷум аз 700cm³ зиёд мекунад, ки ин (2/5)*700cm³ = <<2/5*700=280>>280cm³ мебошад.  
What will the balloon's volume be after the second hour? ** Пас аз соати дуюм, ҳаҷми он (700+280)cm³ = <<(700+280)=980>>980cm³ хоҳад буд.  
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