Me spuds are different colours!

Morning all Bob here,I planted my spuds some time ago in two separate areas in my garden,the spuds come from the same bag from the garden centre,can't remember what type they are,but following kind advice from this forum i decided to dig a few up to see if they are ready.I dug up two plants in one area and they are reds,I then moved over to dig my other area and low and behold they are whites!

Is this common with garden centre spuds,or do you think someone is having a joke with me:eek:.Can't wait to try them tonight with home grown cellary and one of my tomatoes which is ready.Happy days:thumb:

 

could it have been a mixed bag? Hope they're nice and tasty