Overflow and Representing Text Review

Overflow and Representing Text Review

Multiple Choice

Which of the following is NOT true of how computers represent complex information?

• Computing devices use patterns of bits to represent complex information

• Abstraction helps represent complex information by surfacing complexity that might otherwise be hidden

• Depending on context the same sequence of bits may represent different types of information

• Common abstractions that are represented by computing devices include numbers, characters, and color.

Remember this...

Abstraction helps by hiding complexity rather than surfacing it. 

Multiple Choice

Would this statement be considered a form of abstraction "you don't have to know all the details about how a car works in order to operate it."

• Yes because you are taking a something complex and making it simple

• No. Abstraction is when you make something more complex

Multiple Choice

Your computer uses 4 bits to represent decimal numbers (0, 1, 2, 3 and so on) in binary. What is the SMALLEST number for which an overflow error occur?

• 14

• 15

• 16

• 17

Explanation

Your computer uses 4 bits to represent decimal numbers (0, 1, 2, 3 and so on) in binary. What is the SMALLEST number for which an overflow error occur?

Multiple Choice

With a fixed number of bits some numbers are too large to represent in a computer which will lead to overflow errors.

• Using a fixed but large number of bits can eliminate the possibility of round off error when representing numbers in binary

• With a fixed number of bits some numbers are too large to represent in a computer which will lead to overflow errors.

• Using a fixed but large number of bits, for example 128, eliminates the possibility of overflow errors.

• With a large but fixed number of bits it is possible to eliminate either round-off errors or overflow errors, but not both.

Explination

With a fixed amount of bits, no matter how many, at some point the largest possible value will be reached, with 1s for all the bits. Representing the next largest number will lead to an overflow error and the odometer will start back at all 0s.