Question

The number of three digit numbers in which $9$ appears only in one place is

• A. 243
• B. 234
• C. 217
• D. 225

Answer 1

Answer: (D)

225

Answer 2

The number of three digit numbers in which 9 appears at hundred place only is $=1 \times 9 \times 9=81$ Similarly, the number of three digit numbers in which 9 appears at ten or unit place only is
$=(8 \times 1 \times 9) \times 2=144$
So, required number $=81+144=225$