Copyright © University of Cambridge. All rights reserved.
'M, M and M' printed from http://nrich.maths.org/
Try arranging all sets of numbers in order, smallest to biggest.
Which of the five positions are the easiest to fill in?
If you can think of lots of possible values for one space, try to
figure out the highest and the lowest it could be, and whether
there are any other conditions...
Which spaces can you fill straight away?