Three solid shapes A, B and C are similar.
The surface area of shape A is 4 cm^2
The surface area of shape B is 25 cm^2
The ratio of the volume of shape B to the volume of shape C is 27 : 64
Work out the ratio of the height of shape A to the height of shape C.
Give you answer in its simplest form.

Respuesta :

Answer:

[tex]\frac{3}{10}[/tex]

Step-by-step explanation:

step 1

Find the ratio of the height of shape A to the height of shape B

we know that

If two figures are similar, then the ratio of its surface areas is equal to the scale factor squared

Let

z-----> the scale factor

x----> surface area shape A

y----> surface area shape B

so

[tex]z^{2} =\frac{x}{y}[/tex]

substitute

[tex]z^{2} =\frac{4}{25}[/tex]

[tex]z =\frac{2}{5}[/tex]

therefore

the ratio of the height of shape A to the height of shape B is equal to

[tex]\frac{hA}{hB}=\frac{2}{5}[/tex]

step 2

Find the ratio of the height of shape B to the height of shape C

we know that

If two figures are similar, then the ratio of its volumes is equal to the scale factor elevated to the cube

Let

z-----> the scale factor

x----> volume shape B

y----> volume shape C

so

[tex]z^{3} =\frac{x}{y}[/tex]

substitute

[tex]z^{3} =\frac{27}{64}[/tex]

[tex]z =\frac{3}{4}[/tex]

therefore

the ratio of the height of shape B to the height of shape C is equal to

[tex]\frac{hB}{hC}=\frac{3}{4}[/tex]

step 3

Find the ratio of the height of shape A to the height of shape C

we have

[tex]\frac{hA}{hB}=\frac{2}{5}[/tex]

[tex]\frac{hB}{hC}=\frac{3}{4}[/tex]

Multiply

[tex](\frac{hA}{hB})(\frac{hB}{hC})=\frac{hA}{hC}[/tex]

so

[tex](\frac{2}{5})(\frac{3}{4})=\frac{6}{20}=\frac{3}{10}[/tex]