How many 4-digit even numbers can be made from the digits 0, 1, 2, 3, 4 and 5, if no digit is used…

Step 1. Units digit $0$. The other three places use $5$ digits: $5 \times 4 \times 3 = 60$.

Step 2. Units digit $2$ or $4$. That is $2$ ways. The first digit cannot be $0$ or the units digit: $4$ ways. Then $4$ and $3$ ways for the middle places. So $2 \times 4 \times 4 \times 3 = 96$.

Step 3. Add. $60 + 96 = 156$.