Course Content

Python Tutorial for Beginners

1. Introduction to Programming

Writing Lines of Code Challenge 1 Challenge 2

2. Variables in Python

Variables for String Challenge Variables for Numbers Math expressions: Familiar operators Challenge 1 Challenge 2

3. Comments

Comments Challenge 1 Challenge 2

4. If...Else Statement

if statement Comparison operators if-else and if-else-elif statements Challenge 1 Challenge 2

Variables for Numbers

But we can not only assign strings to a variable. You can also assign a number.


              1
            
coins = 70

After writing the code above, every time you call the coins variable in your code, Python will know that you mean 70. You can use this variable in math and more.

Let's see how to add 20 to this variable.


              1
            
print(coins + 20)

Python remembers that coins refers to 70, so it will return 90 (70 + 20 = 90).

Unlike a string, a number does not need to be quoted. This is how Python understands that it is a number with which it can calculate mathematical expressions, and not a text string.

Python can also perform calculations that consist only of variables. For example


              1234
            
price_of_tangerines = 15
price_of_lemon = 7
total_price = price_of_tangerines + price_of_lemon
print(total_price)

The variable total_price now has a value of 22.


              12
            
original_number = 17
original_number = original_number + 8

Let's look at very intresting example.


              123
            
price_1 = "100"
new_price = price_1 + 17
print(new_price)

This code throws an error because Python cannot sum a string and a number.

It's time to practice.

Task

Assign a number (35) to the variable number. Add 5 to the variable number and assign the result to the same variable. Display the result on the screen using print statement.

Task

Assign a number (35) to the variable number. Add 5 to the variable number and assign the result to the same variable. Display the result on the screen using print statement.

Switch to desktop for real-world practiceContinue from where you are using one of the options below

Everything was clear?

Section 2. Chapter 3

Variables for Numbers

But we can not only assign strings to a variable. You can also assign a number.


              1
            
coins = 70

After writing the code above, every time you call the coins variable in your code, Python will know that you mean 70. You can use this variable in math and more.

Let's see how to add 20 to this variable.


              1
            
print(coins + 20)

Python remembers that coins refers to 70, so it will return 90 (70 + 20 = 90).

Unlike a string, a number does not need to be quoted. This is how Python understands that it is a number with which it can calculate mathematical expressions, and not a text string.

Python can also perform calculations that consist only of variables. For example


              1234
            
price_of_tangerines = 15
price_of_lemon = 7
total_price = price_of_tangerines + price_of_lemon
print(total_price)

The variable total_price now has a value of 22.


              12
            
original_number = 17
original_number = original_number + 8

Let's look at very intresting example.


              123
            
price_1 = "100"
new_price = price_1 + 17
print(new_price)

This code throws an error because Python cannot sum a string and a number.

It's time to practice.

Task

Assign a number (35) to the variable number. Add 5 to the variable number and assign the result to the same variable. Display the result on the screen using print statement.

Task

Assign a number (35) to the variable number. Add 5 to the variable number and assign the result to the same variable. Display the result on the screen using print statement.

Switch to desktop for real-world practiceContinue from where you are using one of the options below

Everything was clear?

Section 2. Chapter 3

Variables for Numbers

But we can not only assign strings to a variable. You can also assign a number.


              1
            
coins = 70

After writing the code above, every time you call the coins variable in your code, Python will know that you mean 70. You can use this variable in math and more.

Let's see how to add 20 to this variable.


              1
            
print(coins + 20)

Python remembers that coins refers to 70, so it will return 90 (70 + 20 = 90).

Unlike a string, a number does not need to be quoted. This is how Python understands that it is a number with which it can calculate mathematical expressions, and not a text string.

Python can also perform calculations that consist only of variables. For example


              1234
            
price_of_tangerines = 15
price_of_lemon = 7
total_price = price_of_tangerines + price_of_lemon
print(total_price)

The variable total_price now has a value of 22.


              12
            
original_number = 17
original_number = original_number + 8

Let's look at very intresting example.


              123
            
price_1 = "100"
new_price = price_1 + 17
print(new_price)

This code throws an error because Python cannot sum a string and a number.

It's time to practice.

Task

Assign a number (35) to the variable number. Add 5 to the variable number and assign the result to the same variable. Display the result on the screen using print statement.

Task

Assign a number (35) to the variable number. Add 5 to the variable number and assign the result to the same variable. Display the result on the screen using print statement.

Switch to desktop for real-world practiceContinue from where you are using one of the options below

Everything was clear?

But we can not only assign strings to a variable. You can also assign a number.


              1
            
coins = 70

After writing the code above, every time you call the coins variable in your code, Python will know that you mean 70. You can use this variable in math and more.

Let's see how to add 20 to this variable.


              1
            
print(coins + 20)

Python remembers that coins refers to 70, so it will return 90 (70 + 20 = 90).

Unlike a string, a number does not need to be quoted. This is how Python understands that it is a number with which it can calculate mathematical expressions, and not a text string.

Python can also perform calculations that consist only of variables. For example


              1234
            
price_of_tangerines = 15
price_of_lemon = 7
total_price = price_of_tangerines + price_of_lemon
print(total_price)

The variable total_price now has a value of 22.


              12
            
original_number = 17
original_number = original_number + 8

Let's look at very intresting example.


              123
            
price_1 = "100"
new_price = price_1 + 17
print(new_price)

This code throws an error because Python cannot sum a string and a number.

It's time to practice.

Task

Assign a number (35) to the variable number. Add 5 to the variable number and assign the result to the same variable. Display the result on the screen using print statement.

Switch to desktop for real-world practiceContinue from where you are using one of the options below

Section 2. Chapter 3

Switch to desktop for real-world practiceContinue from where you are using one of the options below