Surgeon Kandiah Chandrakumaran has ended up out of pocket after betting his son Maiuran that he would only achieve a grade C.

Maiuran, who is now planning to take A level maths, said he had been expecting to get a good result.

"I thought all along I would get a B and I was very pleased when I realised I had. My father now owes me £1,000 and I am very pleased about that also."

He said he was planning to spend some of the money on textbooks and a new calculator. He has also agreed to give £250 to his twin sister Keerthana, who is hoping to take a GCSE in information technology next year.

Number games

Mr Chandrakumaran, who works part-time at North Hampshire Hospital in Basingstoke, teaches both children at home.

He said his son's interest in maths came from number games he played with him.

"I taught him from the age of three number tricks and number puzzles. Number crunching is my pastime and I seem to have passed that on to Maiuran. He is very interested in that and decided to sit the exam two years ago.

"He was very excited this morning but I was a bit tense. I thought he would get a C, but he proved me wrong and now I owe him £1,000."

Maiuran, who lives with his father and sister in accommodation at the hospital, sat the exam at Basingstoke College of Technology.