Snapshot surveys of students at Sussex and Sheffield Hallam universities found that many were more confused by the wording of the questions and the tight timing, rather than the maths.
Some 25,000 students were due last Thursday to sit the tests which involved 15 minutes of mental arithmetic questions, delivered by a tape recording, followed by 30 minutes of written arithmetic.
Pat Drake, director of the post-graduate certificate in education at Sussex University, interviewed nine traineeEnglish teachers immediately after the tests. She said: "The difficulty seemed to many of them to be working their way through the wording of the question. Once they knew what they had to do, for some of them the maths was extremely simple."
Separate interviews with students at Sheffield Hallam found that lack of time was the biggest problem.
Meanwhile, two students have told The TES that there was nothing to stop any candidate using a calculator for the mental arithmetic section. Candidates used the same answer book for this section, as for the written section, where calculators were allowed.