Unit 8 · Detecting Reasoning Errors
School Excursion — Teacher Chaperone Logic
Lesson 26 of 34
About this lesson
A school excursion is cancelled if fewer than 20 students sign up, OR if there aren't enough teachers (1 per 10 students). Rohan thinks 2 teachers guarantees the excursion goes ahead. Megan thinks cancellation always means too few students. Both are wrong — each forgot about the other reason.
Chapters
Question
A school excursion to watch a musical at the theatre is scheduled to take place next month. However, it will be cancelled if fewer than twenty students sign up for it. On top of that, even if twenty students or more sign up, there must be enough teachers to accompany them. The school's policy states that there must be at least one teacher looking after every ten students on an excursion.
Rohan: "As long as two teachers are available to accompany the students, the excursion can still go ahead."
Megan: "If the excursion is cancelled, it must be because not enough students signed up for it."
If the information in the box is true, whose reasoning is correct?
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