<PRE><B>Question 82308</B>
1. A cone and a cylinder both have height 48 and radius 15. Give the ratio of their volumes without calculating the two volumes.
:
Vol of a cylinder: V = pi*r^2*h
Vol of cone: V = {{{(pi*r^2*h)/3}}}
:
note that pi*15^2 is common to both equations, so we can eliminate that:
Leaves us with 48 and 48/3:  which gives us ratio of 48:16 or 3:1
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2. A container has the shape of a rectangular solid. Its length is 45cm, width 30cm, and height 20cm. When a rock is submerged, the water level rises 0.5cm. Find the volume of the rock.
:
FInd the volume of a rectangle 45 by 30 by .5; this is the vol of water that was
displaced by the rock:   45*30*.5 = 675 cu cm</PRE>