Question 467008
Start with the formula for the volume of a rectangular pyramid:
{{{V = (1/3)B*h}}} Where B = area of the base of the pyramid (L*W) and h = its perpendicular height.
Let's say that the area of the base of the original pyramid is given by {{{a*b}}} and its height is {{{h}}}.  Its volume is then:
{{{highlight(V[1] = (1/3)abh)}}}
Now we'll double the three dimensions to {{{2a}}}, {{{2b}}}, and {{{2h}}} and find the new volume:
{{{V[2] = (1/3)(2a)(2b)(2h)}}} Simplifying this we get:
{{{highlight_green(V[2] = (1/3)(8)abh)}}}
As you can see, the new volume is 8 times the original volume.