Answer:
30295[tex]mm^3[/tex]
Step-by-step explanation:
V of pencil = V of cone + V of cylinder
let's find V of cone first (you can do cylinder first but I'm getting the hard stuff out first)
V cone = [tex]\frac{1}{3} \pi r^{2} h[/tex]
now plug known values in
[tex]\frac{1}{3}(36)(9)(3.14) =339.12 \\[/tex] [tex]mm^{3}[/tex]
now cylinder
V cyl. = [tex]\pi r^{2} h[/tex]
plugging known values
= [tex](3.14)(6^2)(64) = (3.14)(36)(64)[/tex] = 7234.56 [tex]mm^3[/tex]
add the two values together to find the volume of the crayon
339.12 + 7234.56= 7573. 68[tex]mm^3[/tex]
rounding to nearest millimeter: 7574[tex]mm^3[/tex]