EgmatQuantExpert wrote:
Wildflower wrote:
For a 3 digit number to be even, it has to be either 0 or6.
Constraint: all digits have to be different
Case 1: With 0 as the last digit.
Units digit = 0 --> 1 way
Tens digit can be 3,1,6,7,9, and NOT 0 --> 5 ways
Hundreds digit cannot be 0 and tens digit --> 4 ways
Total = 1 x 5 x 4 = 20 ways
Case 2: With 6 as the last digit
Units digit = 6 --> 1way
Tens digit cannot be 6 --> 5 ways
Hundreds digit cannot be units digit, tens digit, and zero --> 3 ways
Total
Constraint: all digits have to be different
Case 1: With 0 as the last digit.
Units digit = 0 --> 1 way
Tens digit can be 3,1,6,7,9, and NOT 0 --> 5 ways
Hundreds digit cannot be 0 and tens digit --> 4 ways
Total = 1 x 5 x 4 = 20 ways
Case 2: With 6 as the last digit
Units digit = 6 --> 1way
Tens digit cannot be 6 --> 5 ways
Hundreds digit cannot be units digit, tens digit, and zero --> 3 ways
Total
...
.jpg)
