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प्रश्न
Find the number of coins, 1.5 cm is diameter and 0.2 cm thick, to be melted to form a right circular cylinder of height 10 cm and diameter 4.5 cm.
उत्तर
Volume of one coin `=pi xx (1.5)^(2/4) xx 0.2`
Volume of cylinder`= pi xx (4.5)^2 xx 10 /4`
So number of coins to be melted
`="volume of cylinder"/"volume of each coin"`
`=(4.5/1.5) xx 10/0.2`
`= 9 xx 50`
` = 450`
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