# Basic Operators

This section explains how to use basic operators in Python.

### Arithmetic Operators

Just as any other programming languages, the addition, subtraction, multiplication, and division operators can be used with numbers.

number = 1 + 2 * 3 / 4.0

print(number)

Try to predict what the answer will be. Does python follow order of operations?

Another operator available is the modulo (%) operator, which returns the integer remainder of the division. dividend % divisor = remainder.

remainder = 11 % 3

print(remainder)

Using two multiplication symbols makes a power relationship.

squared = 7 ** 2

cubed = 2 ** 3

print(squared)

print(cubed)

Using Operators with Strings

Python supports concatenating strings using the addition operator:

helloworld = "hello" + " " + "world"

print(helloworld)

Python also supports multiplying strings to form a string with a repeating sequence:

lotsofhellos = "hello" * 10

print(lotsofhellos)

Using Operators with Lists

Lists can be joined with the addition operators:

even_numbers = [2,4,6,8]

odd_numbers = [1,3,5,7]

all_numbers = odd_numbers + even_numbers

print(all_numbers)

Just as in strings, Python supports forming new lists with a repeating sequence using the multiplication operator:

print([1,2,3] * 3)

## Exercise

The target of this exercise is to create two lists called `x_list`

and `y_list`

, which contain 10 instances of the variables `x`

and `y`

, respectively. You are also required to create a list called `big_list`

, which contains the variables `x`

and `y`

, 10 times each, by concatenating the two lists you have created.

x = object()

y = object()

```
```# TODO: change this code

x_list = [x]

y_list = [y]

big_list = []

print("x_list contains %d objects" % len(x_list))

print("y_list contains %d objects" % len(y_list))

print("big_list contains %d objects" % len(big_list))

`# testing code`

if x_list.count(x) == 10 and y_list.count(y) == 10:

print("Almost there...")

if big_list.count(x) == 10 and big_list.count(y) == 10:

print("Great!")

Use the online editor below to try out all the codes and if you find any problem please comment below.