Question 10
The source states: “In triangle $ABC$, $D$ is the midpoint of $AB$ and $E$ is the midpoint of $BD$. Point $F$ is on $AB$ such that $E$ is on $CF$. If $BF=5$, compute $BA$.” The supplied key gives 15. Analyse this printed configuration and explain whether that answer is consistent.
Source-consistency warning: the printed incidence conditions and the answer key conflict. Retain the segment names exactly as printed; consider whether named points may coincide. Give a reasoned analysis rather than a guessed correction. This question is assessed manually.
Source-consistency warning: the printed incidence conditions and the answer key conflict. Retain the segment names exactly as printed; consider whether named points may coincide. Give a reasoned analysis rather than a guessed correction. This question is assessed manually.