Question

Two triangular pyramids are similar. The volume of the larger pyramid is 729 cm3 , and the volume of the smaller pyramid is 64 cm3. If the perimeter of the base of the smaller pyramid is 8 cm, what is the perimeter of the base of the larger pyramid? 18 cm 18 cm2 27 cm 27 cm2

Answer 1

Answer:

It's the first option

Step-by-step explanation:

I just answered the question on edge

Answer 2

Answer:   Second Option is correct.

Step-by-step explanation:

Since we have given that

Volume of larger pyramid = 729 cm³

Volume of smaller pyramid = 64 cm³

So, Ratio of volume of larger pyramid to volume of smaller pyramid is given by

$\dfrac{729}{64}=\dfrac{9^3}{4^3}$

So, Ratio of side of larger pyramid to side of smaller pyramid is given by

$\dfrac{9}{4}$

Now, Perimeter of base of smaller pyramid = 8 cm

So, We need to find the perimeter of larger pyramid.

So, it becomes,

$\dfrac{\text{Side of larger pyramid}}{\text{Side of smaller pyramid}}=\dfrac{\text{Perimeter of larger pyramid}}{\text{Perimeter of smaller pyramid}}\\\\\dfrac{9}{4}=\dfrac{x}{8}\\\\x=\dfrac{9\times 8}{4}=\dfrac{72}{4}=18\ cm$

Hence, Perimeter of the base of the larger pyramid is 18 cm².

Therefore, Second Option is correct.