Unit 8 · Detecting Reasoning Errors
Qualification Records — Counting Error
Lesson 15 of 34
About this lesson
Six county records broken, ten qualifiers — Lisa says more than half must be record-breakers. But does 6 records always mean 6 students? Not if one student broke three records. One person, many events: that's the counting trap.
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Question
There are two ways to qualify for the annual Grant County Athletics Championship: by winning at least three local events during the year, or by breaking a county record.
This year, 10 students from Lisa’s school have qualified for the Championship.
Lisa said: “I know that a total of six county records were broken by our students this year. So that means that more than half of our qualifiers must be record-breakers!”
Which one of the following sentences shows the mistake Lisa has made?
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