for part a: is it 1*9*8*7*6*5? or is there more same for part b: is it 1*1*8*7*6*5? or is there more also for part c: is it 2*8*7*6*5*4? or is there more


-the wife and groom don't have to be in the first spot. They can be in any given position, and since order matters, this slightly changes all three answers by one constant apiece. I'll let someone else clarify a little more. -mkburges


The above post is right, your calculation assumes that the bride/groom have to be in the first spot (which is why you multiply the equation with 1 at the start). However, the bride/groom can be in any of the spots in the photo, so we multiply it by 6 instead.

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Recent Math PhD now doing a post-doctorate at UC Riverside.

Kuei-Nuan Lin