Question

Alrighty!!!!!~ Last QUESTION on my geom. review quiz

Can I get some help? *^-^ 40minutes left though cx

Answer 1

The two cones are similar. Find the volume of the larger cone. Round your answer to the nearest hundredth.

A.) 2,025.73 ft^3
B.) 2,850.70 ft^3
C.) 2,980.27 ft^3
D.) 2,999.50 ft^3

Answer 2

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Answer 3

find the volume of small cone and multiply by the sf^3

Answer 4

sf = scale factor

Answer 5

I know that the volume of the small cone is approximately 615.75ft^3

Answer 6

So then my next step would be 615.75 x 3/4 ?

3/4 because it's the scale factor~

Answer 7

volume scales by sf^3

Answer 8

scale factor here is 20/12 right ?

Answer 9

Oh that's right - cubed...

yes it is~

Answer 10

but i reduced it...

Answer 11

\[\text{volume of large cone} = \mathcal{(s.f)^3 \times }(\text{volume of small cone})\]

Answer 12

20/12 = (4*5)/(4*3) = 5/3

it reduces to 5/3, so sf would be 5/3

Answer 13

OH - i reduced it wrong - i see... thanks cx so then

i would multiply the volume of the smaller cone by 5/3 - correct?

Answer 14

But I keep getting the same answer - 1026.25 ft^3 - But that isn't an option >.<

Answer 15

(12/20)^3 = (pi/3)(7)^2(12) / V
V = option B

Answer 16

remember, in a similar objects, the volume ratio equals the cubed of the ratio of their sides

Answer 17

and by sides, i meant the scale factor

Answer 18

That makes sense, i was just confused because i used square instead of cube~ Thanks :3