excuse the double post
POTENTIALLY USEFUL ADVICE FOR THOSE YET TO TAKE THE UKCAT:
I scored 750 on the Quantitative Reasoning section of the UKCAT, but yet i didnt finish the section. Infact out of the 40 questions in the section, i only got to number 25.
I had a bit of a panic basically and about 5 mins from the end, i was only on like question 20, so i just decided i would guess the remaining questions in the last minute. However, i got carried away with another calculation, and before i knew it, the time was up, and i had only answered 25 questions, leaving 15 unanswered. I was so annoyed at myself, and this probably affected my performance in the Abstract reasoning slightly.
Anyway, my point is, i scored 750 after answering 5/8 of the questions. This leads me to the conclusion that perhaps they do not expect you to finish the section, but if you answer a good chunk of it, in an accurate way, you can score highly. Perhaps the score formula is based more on "percentage correct of those answered", than "percentage correct out of all"
Hope this helps, just answer them accurately and work as fast as possible, and dont worry if you cant answer them all