alexzazians
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there's a dat math destroyer question asking: a parking lot has 4 different suvs and 5 different vans. how many ways can the cars be arranged such that one van has to be on either end but 4 suvs must stay together? and the answer explains: 480 because suv arranged is 4 factorial=24 and for the first end there will be 5 vans available, and once its placed, there will be 4 to choose so 5* 4* 24=480 . but i cant get one thing: i agree with the first part: suvs arrange in 4 factorial which 24, but once you place the first van at one end( 5 ), then the other end (4), there will be 3 vans still left that can be arrange? why don't we consider those? and if were not supposed to consider, how can i distinguish these types of questions?
