We chatted on twitter about this question for a bit. What predictions can you make about the predictions that were made? Click through to check your answers!

It's #mathmistake time! What percent of kids got this right? What was the most common wrong answer? Percent on that? pic.twitter.com/lNbaDxUeXx

— Michael Pershan (@mpershan) August 18, 2014

Here are the results from the 59 students who answered this question on an exam:

How would you give feedback to the students who wrote “infinity”?

Imagine that you were to give feedback to the students who wrote “-3/7.” What feedback would you give?