How many 3-digit numbers can be formed by using the digits 1 to 9 if no digit is repeated?
Answers
Answered by
6
digits = 9
let the three digit number is _ _ _
for units place we have 9 options (1,2,3...9 say we write 1) then for tens place we are left with 8 options because repetition is not allowed and similarly for hundreds place we will have 7 options
hence total number of 3 digit number without repetition is 9*8*7 = 504
Similar questions