Unit 8 · Detecting Reasoning Errors
Matt and Yash Chess — Approximation Error
Lesson 7 of 34
About this lesson
Matt won five chess games last week. The overall record says each player wins 'around half.' Mr Stead concludes they must have played about ten games. The word 'around' is the hidden trap — he silently upgraded an approximation to an exact 50/50 split.
Chapters
Question
Matt and Yash play chess together every day at lunch. They are at around the same skill level, and they have each won around half of the matches they've played against each other.
Mr Stead: "I can't remember how many games Matt and Yash played last week, but I know Matt won five, so they must have played about ten games."
Which one of the following sentences shows the mistake Mr Stead has made?
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