Boolean values (True and False) in Python - Cheat Sheet & Quick Revision

Recall & Review

beginner

What are the two Boolean values in Python?

The two Boolean values in Python are True and False. They represent truth and falsehood.

beginner

How do you write the Boolean value for true in Python?

You write it as True with a capital T. Python is case-sensitive, so true is not correct.

beginner

What is the result of the expression 5 > 3 in Python?

The expression 5 > 3 is True because 5 is greater than 3.

beginner

What type does the value True have in Python?

The value True has the type bool, which stands for Boolean.

beginner

How can Boolean values be used in Python programs?

Boolean values are used to control decisions, like in if statements, loops, and to represent conditions that are either true or false.

Which of these is the correct Boolean value for false in Python?

A F

B false

C FALSE

D False

Python Boolean values must be capitalized exactly: False is correct.

What will 3 == 3 return in Python?

A True

B False

C 3

D Error

The expression 3 == 3 checks if 3 equals 3, which is true.

What type is the value True in Python?

A bool

B str

C float

D int

Boolean values like True and False have the type bool.

Which of these expressions evaluates to False?

A 5 == 5

B 10 < 5

C 7 > 3

D 4 == 4

10 < 5 is false because 10 is not less than 5.

In Python, Boolean values are often used in:

A Calculating sums

B Storing text

C Loops and conditions

D Drawing graphics

Booleans control decisions like loops and if statements.

Explain what Boolean values are and how they are used in Python.

Think about yes/no or on/off decisions in programs.

Describe the difference between the Boolean values True and False with examples.

Use simple comparisons to explain.

Practice

1. Which of the following is a Boolean value in Python?

easy

A. yes

B. "True"

C. True

D. 1

Solution

1. Step 1: Understand Boolean values

   Boolean values in Python are exactly True or False, not strings or numbers.

2. Step 2: Identify the correct Boolean

   True is the Boolean value True. "yes", "True", and 1 are not Boolean types.

3. Final Answer:

   True -> Option C

4. Quick Check:

   Boolean = True or False [OK]

Hint: Look for exact True or False without quotes [OK]

Common Mistakes:

• Confusing string "True" with Boolean True
• Using numbers like 1 as Boolean
• Thinking any word means Boolean

2. Which of these is the correct way to write a Boolean value in Python?

easy

A. False

B. true

C. FALSE

D. false

Solution

1. Step 1: Recall Python Boolean syntax

   Python Boolean values start with a capital letter: True and False.

2. Step 2: Check each option

   Only False, False, is correctly capitalized. Others are lowercase or all caps, which are invalid.

3. Final Answer:

   False -> Option A

4. Quick Check:

   Booleans start with uppercase [OK]

Hint: Booleans start with uppercase T or F [OK]

Common Mistakes:

• Writing booleans in lowercase
• Using all uppercase letters
• Confusing with strings

3. What will be the output of this code?

print(5 > 3)

medium

A. Error

B. False

C. 5 > 3

D. True

Solution

1. Step 1: Evaluate the comparison

   The expression 5 > 3 checks if 5 is greater than 3, which is true.

2. Step 2: Understand print output

   Printing a Boolean expression prints True or False accordingly. Here it prints True.

3. Final Answer:

   True -> Option D

4. Quick Check:

   5 > 3 is True [OK]

Hint: Compare values; print shows True or False [OK]

Common Mistakes:

• Thinking it prints the expression as text
• Confusing True with string 'True'
• Expecting an error from comparison

4. Find the error in this code:

if True = 5:
    print("Yes")

medium

A. Assignment used instead of comparison

B. Missing colon after if

C. True cannot be used in conditions

D. Indentation error

Solution

1. Step 1: Check the if statement syntax

   The code uses = which is assignment, not comparison. Conditions need ==.

2. Step 2: Identify the error type

   Using = in an if condition causes a syntax error because assignment is not allowed there.

3. Final Answer:

   Assignment used instead of comparison -> Option A

4. Quick Check:

   Use == for comparison, not = [OK]

Hint: Use == to compare, = is for assigning [OK]

Common Mistakes:

• Using = instead of ==
• Forgetting colon after if
• Thinking True can't be in conditions

5. You want to check if a number n is NOT zero using Boolean logic. Which code correctly prints True if n is not zero, otherwise False?

hard

A. print(n == 0)

B. print(n != 0)

C. print(n = 0)

D. print(not n)

Solution

1. Step 1: Understand the condition

   We want to print True if n is NOT zero, so the condition should check n != 0.

2. Step 2: Evaluate each option

   print(n == 0) prints True if n is zero (wrong). print(n != 0) correctly prints True if n is not zero. print(n = 0) causes a syntax error (invalid syntax). print(not n) prints True if n is zero (because not 0 is True), so it's opposite.

3. Final Answer:

   print(n != 0) -> Option B

4. Quick Check:

   Use != to check not equal [OK]

Hint: Use != to check not equal, not = [OK]

Common Mistakes:

• Using = instead of !=
• Confusing not n with n != 0
• Using == instead of !=