Balls and his Education team fail GCSE maths?

Ed Balls MP, the Secretary of State for Children, Schools and Families, is a man very proud of children's achievements in schools. He also, as the man who would be Chancellor likes to think of himself as a bit of an economics/maths whizz kid.

This makes the following from Parliament from Balls quite funny, because, whilst discussing GCSE questions he said the following,

The third question comes from the mathematics exam, GCSE, June 2008: "Work out 33/4 minus 12/5 " Does the hon. Gentleman (addressing Michael Gove MP) want to try?

I asked the Minister for Schools and Learners (Vernon Coaker MP) a moment ago. He worked it out as two and seven twentieths.. I do hope that he is right.

The Minister for Further Education, Skills, Apprenticeships and Consumer Affairs (Kevin Brennan MP) checked it as well, and he says that that is the right answer.

Two and seven twentieths you say Mr Balls? You say you got this answer from your learned colleague in charge of Schools, and had it double-checked by another learned colleague in charge of further education, and they told you it was right? Why did you not get a bit of paper out yourself?

Let's see, 33/4 as a decimal would be 8.25; and 12/5 as a decimal? That would be 2.4. So... 8.25 minus 2.4 is 5.85. Or as fraction, five and seventeen twentieths. So, where did the two and seven twentieths come from?

Isn't it good to know that the team in charge of schools, from junior minister up to the Secretary of State are so reliable with their figures?

Update: Sadly it seems this is a fomatting error in Hansard's online version and there are missing spaces in the fractions. It should be '3 and 3/4' minus '1 and 2/5' which apparently is '2 and 7/20'. Oh well. I forgot to say in the original, the point being made by Balls is rather weak anyway because you're allowed a calculator in most GCSE maths anyway.