First off, the formula for finding the volume of a cylinder is: V=pi × radius² × height
So, because the diameter is 8 inches, to find radius, we just divide by 2 so R=8÷2=4. The radius is 4 inches.
Then because it said that the height is 3 times the radius, 3×4=12. The height is 12 inches.
Now, we can plug in our information and use the formula to find the volume (V=pi × r² × h) :
V= 3.14×4²×12
=3.14×16×12
=608.88 cubic cm ( it can also be written 608.88 cm³)
And there you have the volume. (If this is wrong, then I apologize. I'm pretty sure it's correct tho. If it is wrong, I'll be happy to try to solve it again for you.)