### Networking Devices and Initial Configuration Module 3.3.3 Number Systems Quiz Answers

**1. What is the binary representation for the decimal number 173?**

- 10100111
- 10100101
- 10101101
- 10110101

**Explanation:** decimal 173 = 128 + 0 + 32 + 0 + 8 + 4 + 0 + 1

**2. How many bits make up an octet in an IPv4 address?**

**Explanation:** An IPv4 address consists of a string of 32 bits divided into four sections called octets. Each octet contains 8 bits (or 1 byte) separated with a dot.

**3. What is the decimal equivalent of 0xC9?**

**Explanation:** 0x refers to the item as hexadecimal. Convert each character into its corresponding nibble. Then combine the nibbles together and calculate the resulting decimal equivalent. C has a value of 12. 12 x 16 = 192. 192 + 9 = 201.

**4. What is the binary representation of 0xCA?**

- 10111010
- 11010101
- 11001010
- 11011010

**Explanation:** When converted, CA in hex is equivalent to 11011010 in binary. One way to do the conversion is one nibble at a time, C = 1100 and A = 1010. Combine the two nibbles gives 11001010.

**5. What is the range of hexadecimal values that can be used in a hextet?**

- 0000 to 1111
- 0000 to ffff
- 1111 to aaaa
- 0000 to 9999

**Explanation:** A hextet is a term used to refer to a segment of 16 bits or four hexadecimal values. A single hexadecimal number is made up with 4 bits, thus the range of a hexadecimal number is from 0 to f. A hextet contains 4 hexadecimal numbers and ranges from 0000 to ffff.

**6. What is the hexadecimal equivalent for the binary number 10011101?**

**Explanation:** Each 4 binary digits equates to 1 hexadecimal digit.

1001 = 9

1101 = 13 (decimal) = D (hexadecimal)

**7. How many bits are in an IPv4 address?**

**Explanation:** An IPv4 address is comprised of 4 octets of binary digits, each containing 8 bits, resulting in a 32-bit address.

**8. A network engineer wants to represent confidential data in binary format. What are the two possible values that the engineer can use? (Choose two.)**

**Explanation:** Binary is a numbering system that consists of the digits 0 and 1 called bits.

**9. What is the hexadecimal equivalent for the decimal number 139?**

**Explanation:** Decimal 139 in binary is 10001011. 128+8+2+1 = 139.

Each 4 binary digits equates to 1 hexadecimal digit.

1000 = 8

1011 = 11 (decimal) = B (hexadecimal)

**10. Which is a valid hexadecimal number?**

**Explanation:** The hexadecimal numbers are 0,1,2,3,4,5,6,7,8,9,a,b,c,d,e,f.. The hexadecimal number 0 represents 0 in decimal and is represented as 0000 in binary. The hexadecimal number f represents 15 in decimal .

**11. What is the binary equivalent of the decimal number 232?**

- 11101000
- 11000110
- 10011000
- 11110010

**Explanation:** 232 in binary is 11101000. 128+64+32+8 = 232

**12. Given the binary address of 11101100 00010001 00001100 00001010, which address does this represent in dotted decimal format?**

- 234.17.10.9
- 234.16.12.10
- 236.17.12.6
- 236.17.12.10

**Explanation:** The binary number 11101100 00010001 00001100 00001010 translates to 236.17.12.10.