CD Collection
Age 14 to 16
ShortChallenge Level 
I have 3 Elvis Presley CDs, 2 Beatles CDs and 1 Queen CD.
How many different ways can they be lined up on a shelf if I must keep all the CDs by the same artist together?
This problem is adapted from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.
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