Java
Learn Java in step-by-step lessons.
Arithmetic Operations
Arithmetic operators
Java has the following operators:
Operator |
Purpose |
Example |
x |
+ |
addition |
x=5+3; |
8 |
+ |
addition |
x=5+3.0; |
8.0 |
- |
minus |
x=5-3; |
2 |
- |
minus |
x=5-3.0; |
2.0 |
* |
multiplication |
x=5*3; |
15 |
* |
multiplication |
x=5*3.0; |
15.0 |
/ |
division |
x=9/2; |
4 |
/ |
division |
x=9/2.0; |
4.5 |
% |
remainder |
x=14%3; |
2 |
An actual program would not use a statement such as X=5+3; it would save time to simply use X=8. An actual program would be more likely to use variables: X=Y+Z; for example.
Note that there is a
times, or
multiplication, operator: *. In algebra, variables are always a single
letter, XY in algebra means X times Y. In programming, variables can be several letters, and we could
not be sure whether XY meant X times Y or a variable called XY.
Notice that operations on two integers results in an integer. If we divide 9/2 we get just 4. If we want 4.5 we must make one of the operands a double or float.
Remainder: %
The % operator is used to find the remainder. Before children learn about decimal numbers, they may
give the answer to division problems as:
"17 divided by 5 is 3 with a remainder of 2" Note that 17/5 results in 3, while 17 % 5 results in 2.
Please study the material at each of the links below.
- The % operator: remainder
- Finding Dozens
- Order of operations
- Calculate Grade
- Algebra to Code
Glossary for arithmetic lessonFull Glossary