



 
Hi Janice, The volume of the conical container is \[\frac13 \; \pi \times 3.5^2 \times 12 = 154 \mbox{ cubic centimeters.}\] The container is $\frac23$ full of sand so the volume of sand in the container is two thirds of 154 cubic centimeters or $\frac23 \times 154$ cubic centimeters. I hope this helps, Janice wrote back
Janice, The conical container and the cone of sand are similar figures. With your interpretation, since the height of the sand is 2/3 the height of the container it must be that the radius of the surface of the sand is 2/3 the radius of the top of the container. Thus the volume of sand is \[\frac13 \; \pi \; \left(\frac23 \times 3.5\right)^2 \times \left(\frac23 \times 12\right) \mbox{ cubic centimeters.}\] Exactly what you have. Penny  


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