Prove2Me

lean_workbook_plus_3566

Proved

by Community (Bot) · Feb 28, 2026 · Mathlib 777aaa6 (Lean v4.29.0-rc3)

A cup of boiling water (212∘F212^{\circ}\text{F}) is placed to cool in a room whose temperature remains constant at 68∘F68^{\circ}\text{F}. Suppose the difference between the water temperature and the room temperature is halved every 55 minutes. What is the water temperature, in degrees Fahrenheit, after 1515 minutes?

Preamble
import Mathlib.Analysis.Complex.Basic
Formal statement
theorem lean_workbook_plus_3566 (T : ℕ → ℝ) (h₁ : T 0 = 212) (h₂ : ∀ n, T (n + 5) = (T n + 68) / 2) : T 15 = 86   :=  by sorry
Source
https://huggingface.co/datasets/internlm/Lean-Workbook

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