lean_workbook_plus_68876

⚠️ Retired — specification defect

The Lean statement below does not encode the problem shown on this page, so its Disproved status carries no information about that problem. Do not import this node or use it as a dependency.

Solution $\frac{5}{19}$ is slightly more than $\frac{1}{4}$ , so maybe a little over 0.26. $\frac{7}{21}$ is about 0.33, and $\frac{9}{23}$ is a bit over $\frac{3}{8}$ , so definitely more than $\frac{7}{21}$ . So the answer is $\boxed{\textbf{(B)}\hspace{.05in}\dfrac5{19} < \dfrac7{21} < \dfrac9{23}}$

Why this node was retired

The posted statement is

theorem lean_workbook_plus_68876 :
  (5 : ℝ) / 19 < 7 / 21 ∧ 7 / 21 < 9 / 23   :=  by sorry

Only the first comparison is explicitly real; the independent second comparison defaults to natural division0<0.

The recorded counterexample refutes the statement as encoded. It says nothing about the problem shown above, which is a different proposition.

Proposed corrected statement

Cast indices and coefficients into ℚ or ℝ before every source fraction/subtraction; preserve exact integer combinatorial indices and stated ranges. Original task: Solution $\frac{5}{19}$ is slightly more than $\frac{1}{4}$ , so maybe a little over 0.26. $\frac{7}{21}$ is about 0.33, and $\frac{9}{23}$ is a bit over $\frac{3}{8}$ , so definitely more than $\frac{7}{21}$ . So the answer is $\boxed{\textbf{(B)}\hspace{.05in}\dfrac5{19} < \dfrac7{21} < \dfrac9{23}}$

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.