One mistake in a maths paper can make an entire exam impossible.
Three different NCEA maths exams have been found to be riddled with errors - with one simple statistics probability question adding up to more than 100 percent.
Maths New Zealand's Jake Wills said the fact there are so many errors shows there's a flaw in the NZQA process.
He said that process should work very well - but mistakes like this, that anyone who sat down and did the exam would have noticed, shows it's not working somewhere.
Wills told Mike Hosking it's not only about the question with mistakes in it. He said students doubt their ability when they can't find an answer.
"One of my students messaged me after the exam and said 'I died because I had no idea how to finish that table, then I didn't even try the next one because I just lost all confidence of knowing how to do it."
LISTEN ABOVE:Â Maths New Zealand's Jake Wills spoke with Mike Hosking
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