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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
$MJ=12$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.