Given : 1, 2, 3, 4, 6, 7 digits.
To find : 3-digit even numbers
Since required number is 3-digit even number, unit’s place can be filled in 3 ways from any one of the even digits 2, 4, 6. Then the remaining two places can be filled in 5P2 ways.
∴ Required = 5P2 x 3 = (5 x 4) x 3 = 60
