Calculating the measurements of a cone can be tricky. Here are some common mistakes that people make:

1. Using the wrong formulas: It’s really important to use the right formulas for finding surface area and volume.

   • The formula for surface area is:
     ( S = \pi r (r + s) )
     (where ( r ) is the radius and ( s ) is the slant height).
   • The formula for volume is:
     ( V = \frac{1}{3} \pi r^2 h )
     (where ( h ) is the height).

2. Mixing up measurements: Sometimes, it's easy to confuse the radius, which is the distance from the center to the edge, with the height, which is how tall the cone is. This can happen often when slant height is involved.

3. Making calculation mistakes: If you don’t do your multiplication or exponent steps correctly, your final answers can be really wrong.

To avoid these problems, always double-check each step you take. Make sure to work carefully and use the same method throughout to get your answers right.