4 + 5 = __ + 3
A student fills the blank with 9 because '4 + 5 = 9 and I stop paying attention after that': the classic equals-sign misconception.
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Free for classrooms, worksheets, slides and other non-commercial use under CC BY-NC 4.0, with credit to Ben Orlin.
Cartoon by Ben Orlin, Math with Bad Drawings. https://cartoons.mathwithbaddrawings.com/2014-01-01-equations-as-balance-scales--4-5-3/ (CC BY-NC 4.0)Transcript
"4 + 5 = __ + 3" Student: "The blank has to be 9, right? Because 4 + 5 = 9 and I stop paying attention after that."