If it is nearly spherical, you can use V = 4πr3 / 3. If the shape is near recatangular, you can obviously just do length x height x width. You can use the known size of the paper (8 1/2″ x 11″) as a comparison for the container.Ĭalculating the volume of a non-cylindrical contianer is a much more challenging feat. Various papers like signup sheets or flyers or whatever are often sitting near the container in question. A useful device for helping with length estimates is a sheet of paper. Note that r (radius) is HALF the diameter. You will need to estimate both r and h of that equation. As we already mentioned above, for a cylindrical object, volume = (area of the base) * height = π r^2 h. If it isn’t close enough, or if you just want to double check your conclusion, you can attempt to calculate the volume by sight. If it looks pretty close, it probably is. Does the container look about the size of any containers of a known volume? A Gallon of milk? A two litre bottle? A 5 gallon bucket? Containers tend to be an exact volume… 750 ml, 2 litres, etc. The best way is to try to use option 3 with an estimated volume. For the stout-hearted, you will need to improvise. If the jar is of the big-brand kind, you can usually find its dimensions & capacity info either on their e-stores, or mentioned in how-to guides (think crafting, food-storing blogs) online.īut what to do in the inevitable scenario of a container that you aren’t allowed to touch and of an unknown volume? For the cowards and weaklings, there’s always option one above. Instead of trying to calculate the volume of the jar, one could try what I did – Look for the brand of the jar (if it is a branded one) and google for its volume instead. You just pop ’round the gorn-and-scumbles, and, Jack’s a doughnut, there you are! edit: MK in the comments gave the following tip which should make this easier and more accurate: You can then use Google (they call it Google Calculator but you use the normal search engine box) to calculate your answer.
For example a search for “ cubic centimeters per gallon” and Google returns “1 US gallon = 3 785.4118 cubic centimeters”. Google is a great too for doing all of this. So, to get your answer, you will want to determine the number of cubic centimeters in the container volume and multiply that number by can simply use a calculator to divide the volume of the container in cubic centimeters by 2.7 (3.375 *. Really 20% is the best value to use for n > 100) It can be assumed that 20% of a given volume is air rather than jellybeans (though for very small or irregularly shaped containers, this figure might be slightly more… never estimate more than 25% air by volume. You need to know:Ī) The approximate volume of one jelly bean can be thought of as a small cylinder 2 cm long and 1.5 cm in diameter (Precisely articulated as: Volume of 1 Jelly Bean = h(pi)(d/2)^2 = 2cm x 3 (1.5cm/2)^2 = 3.375 or 27/8 cubic centimeters)ī) Due to the Jelly Bean spape and irregularities, there is considerable airspace in the container, along with the jelly beans. In fact, it’s almost fool-proof in that situation. This strategy is best if you are “guessing” the number of jellybeans in a known volume. So…ĭon’t count each bean, of course, but if you are allowed to lift the container, you can count the number of jelly beans in one row (remember to compensate for tapering at the bottom of the container) and multiply that number times the number of jellybeans the container is tall. I suspect you wouldn’t be reading this if that’s all you were after, loser.
Arm yourself with the knowledge that there are 930 jelly beans in a US gallon (about 245 / litre) and venture a WAG. In order of increasing complexity, they are: There are a couple of strategies you may use in calculating the number of jellybeans in a jar or other container.
Participant estimates often vary by several orders of magnitude but I believe you can increase your odds and minimize the luck involved with a little knowledge (they say a little knowledge is a dangerous thing, but hey, it’s just a jelly bean contest). For the uninitiated, a jellybean guessing contest (or jellybean counting contest) is a game held at fairs or parties or anyplace, where someone fills a jar or other large, typically transparent container with a known quantity of jellybeans and gives a prize to whomever guesses closest to the actual number.