Variables and their Data Types in JAVA

1. How is a variable in programming different from a variable in math?

• A. In programming, a variable is always a letter that represents an unknown value.

• B. In programming, a variable is a fixed number.

• C. In programming, a variable stores a value and has a name, and the value can change. 

• D. There is no difference — they are the same in both math and programming.

2. What is a variable and why do we use it in programming?

• A. A variable is a command that makes the program repeat.

• B. A variable is a reserved word used to start a method.

• C. A variable is a name used to store data in a program so it can be reused or changed. 

• D. A variable is used only for doing math in a program.

3. Match the following values to the correct Java data types.

a) "Hello"

• A. int

• B. string 

• C. Double 

• D. boolean

4. Match the following values to the correct Java data types.

b) true

• A. char

• B. String

• C. boolean 

• D. int

5. Match the following values to the correct Java data types.

c) 75.5

• A. boolean

• B. double 

• C. int

• D. float

6. Match the following values to the correct Java data types.

d) 25

• A. int 

• B. double

• C. String

• D. char

7. Is this a valid variable name in Java? Why or why not?

int 2hot = 100;

• A. Yes, it’s valid because numbers can be part of variable names.

• B. No, because variable names can’t start with a digit. 

• C. Yes, because Java automatically converts numbers.

• D. No, because you can't use the number 100 in Java.

8. Which of the following is the correct way to declare a variable to store a student’s GPA (as a decimal)?

• A. int GPA = "3.7";

• B. String GPA = 3.7;

• C. double GPA = 3.7; 

• D. boolean GPA = "3.7f";