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Maths Exercices
Variations without repetition
n = m = Vn,m=
Variations with repetition
n = m = VRn,m=
Permutations
n = Pn =
Circular permutations
n = (n-1)!=
Combinations without repetition
n = m = Cn,m=
Combinations with repetition
n = m = CRn,m=

How many natural numbers are there which are greater than 4000 and less than 9000and in which all the figures are different?.

Solution: