QJEEM22Macf9d: JEE Main 2022 Mathematics - Class 11 JEEM22Macf9d Solution: The total number of three-digit numbers, with one digit…

$C - 1:$ All digits are non-zero

${}^9{C_2}\,.\,2\,.\,{{3!} \over 2} = 216$

$C - 2$ : One digit is 0

$0,\,0,\,x \Rightarrow {}^9{C_1}\,.\,1 = 9$

$0,x,\,x \Rightarrow {}^9{C_1}\,.\,2 = 18$

Total $= 216 + 27 = 243$