I froze for a second because I kept second-guessing whether to estimate the helicopter interior volume or account for rotor housing and seats.
Clarify assumptions about the helicopter model and ping pong ball size, then break the problem into estimating the helicopter's interior volume and dividing by the volume of a ping pong ball, accounting for packing efficiency. State your assumptions clearly and walk through the calculation logically, emphasizing your thought process over the exact number.
Pro tip: Acknowledge that this is a Fermi problem where the goal is to demonstrate structured thinking, not to get the 'right' answer. Offer to refine your estimate if given more specific parameters, showing adaptability.
Ask clarifying questions to define the helicopter type (e.g., small passenger vs. cargo) and ping pong ball dimensions (standard 40mm diameter). If no specifics are given, state your assumptions explicitly.
Approximate the helicopter cabin as a simple shape (e.g., rectangular prism or cylinder) using estimated dimensions (length, width, height). Calculate the volume in cubic meters or centimeters.
Compute the volume of a single ping pong ball using the formula for a sphere (4/3 * π * r^3) with radius 2 cm, giving approximately 33.5 cm³.
Apply a packing factor (e.g., 0.64 for random close packing of spheres) to account for the empty space between balls. Divide the helicopter volume by the ball volume and multiply by the packing factor.
Round to a reasonable order of magnitude, and briefly sanity-check the result (e.g., does it seem plausible?). Present the final estimate with a clear summary of assumptions and calculations.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.