# Permutation and Combinations Practice [Arranging the reindeer]

**How many ways can you arrange your reindeer?**

**Below you see the solution given:**

**1)First perform a normal permutation ignoring that you have to keep Gloopin and Lancer apart; so the first part of the solution = 4*3*2*1. So far so gut.**

**2)We can count the number of arrangements where Gloopin and Lancer are together by treating them as one double-reindeer. Now we can use the same idea as before to come up with 3⋅2⋅1=63, dot, 2, dot, 1, equals, 6 different arrangements. But that's not quite right.**

**3)Why? Because you can arrange the double-reindeer with Gloopin in front or with Lancer in front, and those are different arrangements! So the actual number of arrangements with Gloopin and Lancer together is 6⋅2=12**

**Out of this solution I really do not understand the explanation in "2)"; I mean how do you know**

**which is the arrangement where Glopin and Lancer are together? In general I will be really**

**thankful if someone could explain me the whole logic ["2)" and "3)"] here.**

**Thank you in advance,**

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