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Question 1

What is the Java data type used for true/false values?

Answer 1

boolean

Question 2

What are the possible values of a boolean type?

Answer 2

true and false

Question 3

What is an example of declaring a boolean variable?

Answer 3

boolean isJavaFun = true;

Question 4

Can a boolean store values other than true or false?

Answer 4

No, it can only hold true or false.

Question 5

How do you print a boolean value in Java?

Answer 5

System.out.println(isJavaFun);

Question 6

What is the output of System.out.println(5 > 3);?

Answer 6

true

Question 7

What is the output of System.out.println(10 == 15);?

Answer 7

false

Question 8

What is the result of boolean b = (1 > 2);

Answer 8

false

Question 9

What is a boolean expression in Java?

Answer 9

An expression that returns true or false.

Question 10

What operator is used to check if two values are equal?

Answer 10

==

Question 11

What operator checks if a value is not equal?

Answer 11

!=

Question 12

What will System.out.println(10 >= 9); output?

Answer 12

true

Question 13

What are relational operators used for?

Answer 13

To compare values and return a boolean result.

Question 14

What is the Java equivalent of the mathematical symbol ≤?

Answer 14

<=

Question 15

What does > check for?

Answer 15

If one value is greater than another.

Question 16

What does System.out.println(10 < 5); output?

Answer 16

false

Question 17

How does != behave?

Answer 17

Returns true if values are not equal, otherwise false.

Question 18

What will System.out.println(100 == 100); output?

Answer 18

true

Question 19

What does System.out.println(5 == 5); return?

Answer 19

true

Question 20

How would you check if x is greater than y in Java?

Answer 20

x > y

Question 21

What is the output of System.out.println(8 <= 8);?

Answer 21

true

Question 22

What is the output of System.out.println(3 != 3);?

Answer 22

false

Question 23

How are boolean expressions commonly used?

Answer 23

In conditions for if statements and loops.

Question 24

How do you check if a variable age is at least 18?

Answer 24

age >= 18

Question 25

What happens when you compare true == false?

Answer 25

It evaluates to false.

Question 26

What does System.out.println(0 == false); return?

Answer 26

Compilation error (boolean is not directly comparable to integers).

Question 27

How do you use a boolean in an if statement?

Answer 27

if (isJavaFun) { System.out.println("Java is fun!"); }

Question 28

What will System.out.println(!true); output?

Answer 28

false

Question 29

What does ! do in a boolean expression?

Answer 29

It negates the boolean value (true becomes false, and vice versa).

Question 30

What will System.out.println(!(10 > 5)); output?

Answer 30

false