A sculpture is formed from a square-based pyramid resting on a cuboid. The base of the cuboid and the base of the pyramid are both squares
of side 3 cm.
The height of the cuboid is 8 cm and the total height
of the sculpture is 15 cm.
The total mass of the sculpture is 738g.
15 cm
8 cm
3 cm
The cuboid-part of the sculpture is made of iron
with density 7.8 g/cmº.
The pyramid is made from copper.
Calculate the density, in g/cm', of the copper.
[The volume of a pyramid is:
3
-* area of base x perpendicular height.)
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