thereddevils
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Axiom17
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What's your attempt so far? I.e. method and calculations? 
njama
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Hint: It is Pyramidal Frustum. Correct me if I am wrong.
Axiom17
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njama said:
No that's what I was thinking too
cheers njama on posting the link OK, so thereddevils give that a go now!
thereddevils
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Axiom17 said:No that's what I was thinking too
OK, so thereddevils give that a go now!
ok so from the formula for volume of a pyramidal frustum is given by
V=1/3(A1 + A2 + root(A1)(A2))(h)
the height is root(18)
A1=100 , A2=16
i got V=220 cm^3
but the answer given is 312 cm^3.
Axiom17
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Yes the formula is:
[tex]V=\frac{1}{3}h \left( A_{1}+A_{2}+\sqrt{A_{1}\times A_{2}} \right)[/tex]
Where [itex]A_{1}[/itex] is the bottom area, [itex]A_{2}[/itex] is the top area, and [itex]h[/itex] is the height. Refer to your diagram for these values.
If you check that you're using all of the correct values , then you'll get the answer.
[tex]V=\frac{1}{3}h \left( A_{1}+A_{2}+\sqrt{A_{1}\times A_{2}} \right)[/tex]
Where [itex]A_{1}[/itex] is the bottom area, [itex]A_{2}[/itex] is the top area, and [itex]h[/itex] is the height. Refer to your diagram for these values.
If you check that you're using all of the correct values
, then you'll get the answer.