In a hress-point testcross, it was found the genetic map for three linked genes was A---20cM---B---10cM---C If a cross was performed to estimate the...

In a hress-point testcross, it was found the genetic map for three linked genes was A---20cM---B---10cM---C

If a cross was performed to estimate the map distance between genes A and C only. how would this distance compare to the sum of the distances A-B and B-C? Explain why.