I need to know how to find the volume of the smaller cube
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Let's calculate the similarity scale:
[tex]k=\dfrac{2}{5}[/tex]
The quotient of the volume of similar prism is equal to the cube of the similarity scale:
[tex]\dfrac{V_1}{V_2}=k^3[/tex]
Substitute:
[tex] k=\dfrac{2}{5},\ V_2=60\ cm^3\\\\\dfrac{V_1}{60}=\left(\dfrac{2}{5}\right)^3\\\\\dfrac{V_1}{60}=\dfrac{8}{125}\ \ \ \ |\cdot60\\\\V_1=\dfrac{8}{125}\cdot60\\\\V_1=\dfrac{8}{25}\cdot12\\\\V_1=\dfrac{96}{25}\ cm^3\to V_1=3.84\ cm^3 [/tex]