Q. How many even numbers of 3 different digits can be formed from the digits 1, 2, 3, 4, 5, 6, 7, 8, 9 (repetition of digits is not allowed)?
A) 224
B) 280
C) 324
D) None of these
Explanation
(a)
The number will be even if last digit is either 2, 4, 6 or 8 $ie$ the last digit can be filled in 4 ways and remaining two digits can be filled in $\ ^{8}P_{2}$ ways. Hence, required number of number of three different digits $= \ ^{8}P_{2} \times 4 = 224$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.