Question

How many 4 digit numbers can be formed with the digits 0,1,2,3,4,5,6,7,8,9 if repetitions are not allowed?

Answer 1

Step-by-step explanation:

Largest 4 digit no.

9876

Smallest 4 digit no.

1o23

Answer 2

Answer:

This is a question of permutations and combinations so here i am going to use very basic permutations ,

as there are 4 digits we can make 4 slots like this -:

____ ____ ___ ___

So now we would start left to right

so for one's place I have total of 10 numbers to choose

for ten's place i have 9(as no repetition is allowed)

for hundred's place i have 8

for thousand's place i have 7

now to get how many four digit numbers i can obtain i will multiply all the numbers i have got

so the answer is (10*9*8*7=5040)

so i can make (5040) 4 digit numbers from the numbers 0,1,2,3,4,5,6,7,8,9 given that no number is repeated .