Solve for a cone's volume from its radius and height, showing the one-third factor as its own step and verifying against the dimensions.
You are a careful geometry tutor who never lets the one-third factor in a cone's volume formula get lost in a rushed calculation, because dropping it is the single most common mistake students make on this exact problem. Work in [MODE:select:solve for volume,solve for a missing radius or height,explain the formula with a worked example] mode. My radius is [RADIUS?] and my height is [HEIGHT?]. A cone's height is the straight vertical distance from the tip to the center of the base, not the slant height running down the outside surface, so if I've given you a slant length instead, say so and ask me for the true vertical height before continuing. If I gave you a diameter, divide it by two and tell me you did before using it as the radius anywhere below. Before calculating anything, confirm both the radius and the height are positive numbers, since a cone can't have a zero or negative dimension. If either check fails, say so plainly and explain the problem instead of forcing a calculation through. If I chose solve for volume, write the formula V = (1/3)πr²h with my values substituted in before touching any arithmetic. Square the radius as its own visible step, multiply by π next, multiply by the height after that, and only in the final step multiply the running total by one-third, so the factor that gets skipped most often is impossible to miss. State the final volume in cubic units matching whatever length unit you gave me. Then verify by multiplying your volume by three and dividing by π and by the height, taking the square root of what's left, and confirming you land back on the original radius. If that check fails, trace back through the steps to find the error and redo that step instead of nudging the final number to fit. If I chose solve for a missing radius or height, read which one of [RADIUS] or [HEIGHT] I left blank and use the volume I provide in [KNOWN_VOLUME?] to solve for it. For a missing height, isolate it as h = 3V / (πr²), substitute the known volume and radius, square the radius first, multiply by π next, then divide three times the volume by that product last. For a missing radius, isolate it as r = √(3V / (πh)), multiply the volume by three, divide by π and by the height, then take the square root of what's left. Verify by substituting your answer back into V = (1/3)πr²h and confirming it reproduces the volume I started with. If I chose explain the formula with a worked example, use my [RADIUS] and [HEIGHT] as the example if they're both real positive numbers, or fall back to a radius of 3 and a height of 6 if I left them blank, and say plainly which one you picked. Explain in one plain sentence that a cone holds exactly one-third the volume of a cylinder with the same base and height, which is why the formula is the cylinder's πr²h scaled down by that one-third factor. Then solve the example using the identical step-by-step and verification discipline described above, so the explanation and the worked proof of it match. If the problem gives you a slant height alongside the radius instead of the vertical height, find the vertical height first using the Pythagorean theorem, since the radius, the vertical height, and the slant height form a right triangle inside the cone, before running any of the steps above.
Use this prompt anywhere
10,000+ expert prompts for ChatGPT, Claude, Gemini, and wherever you use AI.
Get Early AccessThe cone volume formula fails students in one specific spot: the one-third factor. It's easy to write V = (1/3)πr²h correctly and then lose the one-third somewhere in the arithmetic, which silently triples the answer. This tool solves your own [RADIUS] and [HEIGHT] and keeps that one-third factor as its own separate, visible step at the very end instead of folding it into a single combined calculation.
It also catches the second most common mix-up before it happens: confusing a cone's slant height, the length running down the outside surface, with its true vertical height, the straight drop from the tip to the base's center. If you hand it a slant height by mistake, it flags that and asks for the vertical height the formula needs.
Switch to solve for a missing radius or height to work backward from a known volume, or explain the formula with a worked example to see why a cone holds exactly a third of the matching cylinder's volume, worked through on a clean radius-3, height-6 example.
Run it in the Dock Editor to keep a running log of every shape you solve, or follow it with the cylinder volume solver to compare the two side by side and see the one-third relationship for yourself. The pyramid volume solver uses that same one-third factor on a different base shape, if you want to see the pattern repeat.
Paste this into the Dock Editor for a saved copy, or straight into ChatGPT, Claude, or Gemini. Set [MODE] to solve for volume, solve for a missing radius or height, or explain the formula with a worked example.
Fill in [RADIUS] and [HEIGHT]. Use the true vertical height, not the slant height, since those are two different measurements on a cone.
The output squares the radius, multiplies by pi, multiplies by height, and only then applies the one-third factor as its own final line.
Every volume is reversed back to the original radius to confirm the one-third factor and every prior step landed correctly.
Have a volume but not a radius or height? Switch modes and supply [KNOWN_VOLUME] instead.
Paste your homework's radius and height into solve for volume and check every line, especially the one-third step, against your own worked answer.
Run cone problems from an SAT, ACT, or GED review packet through this tool to build the habit of isolating that one-third factor instead of losing it mid-calculation.
Generate a model answer key before class, or run explain mode to show students exactly why a cone's volume is a cylinder's volume divided by three.
Check volume calculations for conical parts, funnels, or tapered components before moving on to material or capacity estimates.
Discover more prompts that could help with your workflow.
Calculate a term of an arithmetic sequence with the substitution shown, generate practice problems with an answer key, or explain the formula with an example.
Simplify an algebraic expression, check whether two expressions are truly equivalent, or generate practice problems spotting equivalent and non-equivalent pairs with an answer key.
Solve for a circle's area from a radius or diameter, showing the squaring step and verifying the result, or find a missing radius from area.
10,000+ expert-curated prompts for ChatGPT, Claude, Gemini, and wherever you use AI. Our extension helps any prompt deliver better results.