The State Examinations Commission has confirmed there was a mistake in the Irish-language version of Monday's Higher Level Maths Leaving Cert exam.
Pupils were left puzzled after a mathematical formula was incorrectly translated from English in paper two.
Niall Mac Uidhilin told Iris Aniar on RTÉ Raidió na Gaeltachta that his daughter was left bewildered when she discovered the error and thought that the fault lay with her own lack of understanding.
"She had already done two pages of work on the question, so she had wasted a certain amount of time, and then she had to go and find another question to answer instead," he said.
"She thought there was something she hadn’t seen or understood, that she was the problem."
Eoghan Ó Ceallaigh, Principal of Coláiste na Coiribe in Galway, said: "Most students probably didn’t understand that it was a mistake.
"There’s no fixing it now, the error happened, and it might have brought additional stress for pupils.
"The main thing for me now is that there is equality for all students, and the State Examinations Commission now has to look at that and come up with a marking scheme that makes sure it’s fair for all the students who sat the paper through Irish."
A spokesperson for the SEC confirmed that there was an error in the Irish version of question 8(b) of the Higher Level Mathematics paper two.
"This error may have been a cause of confusion for candidates which is regretted by the SEC," the spokesperson said.
"The SEC operates within the core principle that candidates cannot be disadvantaged as a result of an error on an examination paper.
"As outlined in the protocol, this will be taken fully into account when marking the work of candidates who answered the paper through Irish.
"The marking scheme will, as usual, be published along with those in all other subjects after the issue of results."
The SEC said 25,867 candidates entered to sit Higher Level Mathematics of which 2,057 initially entered to sit the paper through Irish.
The actual number of candidates sitting the exam will not be available until the issue of results.
