We have,
0,1,3,4,6,7
For three-digit even number, it must end with either 0,4,6
The number of three -digit even numbers ending with 0 is
=5×4=20
The number of three -digit even numbers ending with 4
=4×4=16
The number of three -digit even numbers ending with 6
=4×4=16
Total three digits even numbers =20+16+16=52