Digital Number Systems Quiz

Which number system is used to store information digitally in a computer?

• Decimal (base 10)

• Binary (base 2)

• Octal (base 8)

• Hexadecimal (base 16)

How many different digits are used in the Hexadecimal number system?

• 2

• 10

• 8

• 16

Answer explanation

The Hexadecimal number system uses 16 digits (0 1 2 3 4 5 6 7 8 9 A B C D E F)

How many different values can be represented using 4 bits?

• 4 different values

• 8 different values

• 16 different values

• 32 different values

Answer explanation

4 bits can encode 2^4 = 16 different values

Which of the following pixels has a color value of #00ff00 (expressed in hexadecimal)?

• White Pixel

• Blue Pixel

• Red Pixel

• Green Pixel

If black is 0 and white is 1, which of the following binary codes creates the smiley face pixel image below?

• 00100100 00000000 01000010 00111100 00000000

• 11011011 11111111 10111101 11000011 11111111

• 00111000 01000000 00111000 11111111 00000000

• 01010101 10101010 01010101 10101010 01010101

Consider the following numbers: - The decimal value 10₁₀ - The binary value 1001₂ - Hexadecimal value C₁₆ Which of the following lists the numbers in order from least to greatest?

• 1001₂, 10₁₀, C₁₆

• 10₁₀, 1001₂, C₁₆

• 10₁₀, C₁₆, 1001₂

• C₁₆, 1001₁, 10₁₀

Answer explanation

Let’s convert each value to decimal. 10 (decimal) is 10 (decimal), 1001 (binary) is 9 (decimal), and C (hexadecimal) is 12 (decimal). So least to greatest is 1001 (binary), 10 (decimal), C (hexadecimal), or 9, 10, 11 (decimal)

The RGB encoding scheme encodes a color using 24 bit sequences. The first 8 bits encode the amount of red in the color, the next 8 bits encode the amount of green in the color, and the last 8 bits encode the amount of blue in the color. Which of the following is a true statement about the color encoded by this binary sequence:

• This color is mostly red.

• This color is mostly green.

• This color is mostly blue.

• This color has no blue in it.

What is data abstraction?

• Manipulating data to create something new

• Storing data in as little space as possible

• The process of simplifying complicated data into manageable chunks

• Filtering data to gain new knowledge

Which of the following are examples of encoding information?

• Representing fast food meals as numbers on the menu. For example a number 1 represents a hamburger.

• Assigning a numeric value to every area of a region, for example zip codes in the United States

• Assigning a number to every character of the alphabet so we can represent sentences as series of simple digits.

• all answer choices are correct

What is the number base of the binary number system?

• 10

• 2

• 1

• 0