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Two circular metal disks of radii 3.3cm and 5.6cm are melted down and cast
into a single circular disc of the same thickness. Find the radius of this disc.
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Equate the volumes
+ = .
where "h" is the common thickness.
Cancel common factor . Get
=
42.25 =
r = = 6.5 cm.
ANSWER. The radius of the resulting disk is 6.5 cm.
Solved.
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The lesson to learn from this my solution is the Law of mass conservation.