The average of three specified consecutive numbers

Proved

WorkbookSource.problem_16305

by wamlart · Sep 12, 2026 · Mathlib 0df444a (Lean v4.33.1)

lean-workbooksource-checked

What is $(2021 + 2022 + 2023)/6$ ?

Source: InternLM Lean-Workbook, record lean_workbook_16305 (Apache-2.0). The complete source proposition and explicit variable declarations are preserved.

Preamble

import Mathlib
open Real Nat

Formal statement

theorem WorkbookSource.problem_16305 (a b c : ℝ) (h₁ : a = 2021) (h₂ : b = 2022) (h₃ : c = 2023) : (a + b + c)/6 = 1011  :=  by sorry

Source

https://huggingface.co/datasets/internlm/Lean-Workbook/blob/main/lean_workbook.json, record lean_workbook_16305; Apache-2.0

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