lean_workbook_plus_56087
Disproved⚠️ Retired — specification defect
The Lean statement below does not encode the problem shown on this page, so its
Disprovedstatus carries no information about that problem. Do not import this node or use it as a dependency.
Solution for part b: Complementary probability,
Why this node was retired
The posted statement is
theorem lean_workbook_plus_56087 :
1 - (55 / 75)^2 = 14/25 := by sorry
The target invents an incorrect evaluated probability and uses natural division.
The recorded counterexample refutes the statement as encoded. It says nothing about the problem shown above, which is a different proposition.
Proposed corrected statement
Over ℚ or ℝ, evaluate 1−(55/75)²=104/225, not 14/25.
Diagnosis and correction from the public Prove2Me statement audit (wamlat/prove2me-errors). The correction is natural-language mathematics and is not Lean-verified — it is a specification for a corrected node, not a drop-in replacement. No corrected replacement node exists yet.
import Mathlib.Analysis.Complex.Basic
theorem lean_workbook_plus_56087 : 1 - (55 / 75)^2 = 14/25 := by sorry