Most Important Selected Qs for JEE AdvancedMathematicsPermutation and Combination
The number of five digit numbers that can be formed using its digits 1,2,3,4,5,6,7,8,9 in which one digit appears once and two digits appear twice (e.g. 44533) is k then the value of k 1890 is equal to
Correct answer
4
Step-by-step solution
^9 C ₃ ^3 C ₂ 5! 2!2!1!