How many 3 digit even numbers can we form with numbers from $\{0,1,2,3,4,5,6,7 \}$?

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How many 3 digit even numbers can we form with numbers from $\{0,1,2,3,4,5,6,7 \}$?
My work : We have to count numbers of the form $\overline{abc}$.
$a$ can take $7$ values, $b$ can take $8$ values and $c$ can take $4$ values.Hence, there are $7\times 8 \times 4=224$ numbers. Is this correct?
EDIT: It seems that my answer is correct. Now, how to count the numbers if I am not allowed to repeat digits?