Maths

How many silver coins, 2cm in diameter and of thickness 2 mm, must be melted to form a showpiece in the form of a frustum of a cone having height 9 cm and radii of the outer circular ends as 5cm and 3cm?

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asked by Simran
  1. if the cone were complete, it would have height 45/2, so the missing part has height 27/2.

    So, if there are x coins,

    (π*0.2*1^2)x = π/3 (5^2*45/2 - 3^2*27/2)
    x = 735

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    posted by Steve
  2. l asked for 3 marks ,please reput in step bystep

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    posted by jai

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