Edexcel S1 June 2011 - Normal Distribution

I have been looking at the Edexcel S1 paper for June 2011 and in particular Q4b on Normal Distribution. The answer to Q4b is given as 15.28 however the way the question is worded is says 'the fastest 30%' which I have interpreted as a z value of 0.7. Why does the correct answer use a value of 0.3 ie a value to the left of the mean? If the mean for the distribution is 16.12 then surely the fastest 30% of children must score higher than 16.12 not lower as the answer implies. What am I not getting here?

Mate, it's a race. The smaller/shorter the time the better.