Mark marked out the points $J$, $K$, $L$ and $M$ on a straight line, so that $JK=13$cm, $KL=11$cm, $LM=14$cm and $MJ=12$cm. What is the distance, in cm, between the two points furthest apart?

If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.

This problem is taken from the UKMT Mathematical Challenges.