Sunday Times Teaser 2795 – No Mean Feat
by Nick MacKinnon
Published: 17 April 2016 (link)
I bought a run of consecutively-numbered raffle tickets, some of which were red and the rest were blue. Amongst my numbers no red number was the average of two other reds, and no blue number was the average of two other blues. I actually won the raffle. My two-figure winning red number was in fact the geometric mean of two other red numbers of mine. [The geometric mean of M and N is the square root of MxN.]
What were my blue numbers?