Unit 1 Digital Information Review

Which of the following best describes how computing devices represent information?

• A computer will either represent information as bits or bytes but not both

• A computer represents data as a byte which is either a 0 or a 1.

• A computer represents data as bits which is either a 0 or a 1.

• A computer represents information as bits which contain 8 bytes.

How many numbers can be represented with an 8-bit binary system?

• 128

• 256

• 127

• 255

What is the minimum number of bits you would need to encode the 26 letters of the alphabet plus a space - a total of 27 characters?

• 2 bits

• 3 bits

• 5 bits

• 6 bits

Convert the decimal (base-10) number 129 to binary (base-2).

• 1000 0001

• 1100 0001

• 0110 0110

• 0001 1111

What is the 4-bit binary number for the decimal number 10? 

• 0010

• 1010

• 0110

• 0101

Convert the binary (base-2) number 0011 0001 to decimal (base-10).

• 49

• 64

• 32

• 121

Number systems with different bases such as binary (base-2) and decimal

(base-10) are all used to view and represent digital data. Which of the following is NOT true about representing digital data?  

• At one of the lowest levels of abstraction, all digital data can be represented in binary using only combinations of the digits zero and one.

• The same value (number) can have a different representation depending on the number system used to represent it.

• Groups of bits can be used to represent abstractions, including but not limited to numbers and characters.

• Some large numbers cannot be represented in binary and can only be represented in decimal.

The position of a runner in a race is a type of analog data. The runner’s position is tracked using sensors. Which of the following best describes how the position of the runner is represented digitally?  

• The position of the runner is determined by calculating the time difference between the start and the end of the race and making an estimation based on the runner’s average speed.

• The position of the runner is measured and rounded to either 0 or 1 depending on whether the runner is closer to the starting line or closer to the finish line.

• The position of the runner is predicted using a model based on performance data captured from previous races.

• The position of the runner is sampled at regular intervals to approximate the real-word position, and a sequence of bits is used to represent each sample.

Which of the following lists the values in order from least to greatest?  

• Binary 1001, Decimal 7, Decimal 13, Binary 1011

• Decimal 7, Binary 1001, Binary 1011, Decimal 13

• Binary 1011, Binary 1001, Decimal 7, Decimal 13

• Binary 1001, Binary 1011, Decimal 7, Decimal 13

Which of the following can be represented by a sequence of bits?

I. An integer II. A character III. A sound wave   

• I only

• II only

• I and II only

• I, II, and III