convert decimal 20 to binary. make sure you list all eight bits.

Answer:

00010100

Explanation:

Step1: Divide by 2 and get remainders

$20\div2 = 10$ remainder $0$

Step2: Divide quotient by 2 again

$10\div2 = 5$ remainder $0$

Step3: Divide new quotient by 2

$5\div2 = 2$ remainder $1$

Step4: Divide new quotient by 2

$2\div2 = 1$ remainder $0$

Step5: Divide new quotient by 2

$1\div2 = 0$ remainder $1$

Step6: Read remainders in reverse

Read $10100$ in reverse order.

Step7: Pad to 8 - bits

Since we need 8 - bits and we have 5 - bits, pad with 3 leading 0s to get 00010100.