Today I decided to cook something, but then I realized there is a critical item missing − a measuring glass. Being a programmer and all, I decided this wouldn't be much of a problem, as I could probably graduate it knowing its radius and height.
Height is 10cm and radius is 6cm. From the formula V = pi*r^2*h I got 1.13097336 liters, which is not possible because its volume is definitely below 0.5 liters.
I'd like to know how could I mess up such a simple formula, and then I'd like to figure out a way to graduate the glass knowing its volume, preferably in 25ml increments.
Yours calculations are correct, given the measures you've provided us. Maybe 6cm is the diameter of the container, so its radius is 3. That would make the volume you calculated go down by a factor of 4, making it 282.7 ml. Given your constraint that it is definitely below 0.5 liters, that seems correct.
About the increments, you could calculate the height of a cylinder whose volume is 25ml and radius is r, and then use a ruler to make marks.
h = V/(pi*r^2). Remember to use the correct units. For a radius of 0.03 meters (3cm), that would be approximately 0.00884194128 meters, or 0.88 cm.