# Operators

## Let’s do Math: Arithmetic Operator

In the last exercise, we learned about variables and how we can assign values to a variable of a specific type, such as:

int age = 3;  // declare variable age of type int with value 3
age = 4;      // assign 4 to the variable age


Looking at the code above, it essentially adds 1 to the value of the variable age.

And, in Java, we can perform math operations on variables directly with arithmetic operators: +, -, *, /, %. For example, we can use the add operator + to add 1 to age:

int age = 3;  // declare variable age of type int with value 3
age = age + 1;// add 1 to age


### Instructions

1. Use the program below to practice using the arithmetic operators. Change the numbers to see the answers.

## Comparisons: Relational Operator

Next, let’s learn how to compare numbers, using relational operators.

Just like in math, we can compare numbers using >, <, >=, <=. For example: (3 > 2) is true, a boolean value.

### Comparison Practice

1. Use the program below to practice using the comparison operators. Change the numbers to see the answers.

## Exam Statistics!

Patrick 🐥 and 4 of his classmates just had a music exam in this class. These are the grades of their exams: Patrick(88), Tom(89), Mary(95), Chris(84), Jen(92).

We want to produce a grade statistic report of the whole class.

This report lists each student’s grade, class average score, and whether class average is over 60, 70, 80, 90 (true or false), like the following:

---------------------------
---------------------------