Python Program to Add Two Numbers

To understand this example, you should have the knowledge of the following Python programming topics:

In the program below, we've used the `+` operator to add two numbers.

``````# This program adds two numbers

num1 = 1.5
num2 = 6.3

sum = num1 + num2

# Display the sum
print('The sum of {0} and {1} is {2}'.format(num1, num2, sum))
``````

Output

`The sum of 1.5 and 6.3 is 7.8`

The program below calculates the sum of two numbers entered by the user.

Example 2: Add Two Numbers With User Input

``````# Store input numbers
num1 = input('Enter first number: ')
num2 = input('Enter second number: ')

sum = float(num1) + float(num2)

# Display the sum
print('The sum of {0} and {1} is {2}'.format(num1, num2, sum))
``````

Output

```Enter first number: 1.5
Enter second number: 6.3
The sum of 1.5 and 6.3 is 7.8```

In this program, we asked the user to enter two numbers and this program displays the sum of two numbers entered by user.

We use the built-in function input() to take the input. Since, `input()` returns a string, we convert the string into number using the float() function. Then, the numbers are added.

Alternative to this, we can perform this addition in a single statement without using any variables as follows.

``````print('The sum is %.1f' %(float(input('Enter first number: ')) + float(input('Enter second number: '))))
``````

Output

```Enter first number: 1.5
Enter second number: 6.3
The sum of 1.5 and 6.3 is 7.8```

Although this program uses no variable (memory efficient), it is harder to read.

Before we wrap up, let's put your understanding of this example to the test! Can you solve the following challenge?

Challenge:

Write a function to add 10 to a given number.

• For example, for input 5, the output should be 15.