Python 3b - Simple Calculations
Simple Calculations in Python
You can perform calculations on numbers in Python using the four main operators:
print(89 + 47)
print(89 - 47)
print(89 * 47)
print(89 / 47)
=
136
42
4183
1.8936170212765957
For addition, use the plus sign +
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To subtract numbers, use the dash symbol – (but not an underscore _ )
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For multiplication, use an asterisk * which can be made by pressing Shift and 8 on a typical keyboard.
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To divide numbers, use a forward slash / (but not a backslash \ )
Use a string and the calculation to make the output user friendly.
print("53 x 7 =" , 53 * 7)
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53 x 7 = 371
Simple Calculations Task 1 (+ - * /)
Print four different simple calculations, using a different operator ( + - * / ) for each.
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Make the output user friendly by also showing the calculation (not just the answer).
Copy the divide symbol here using Ctrl and C: ÷
Example solution:
18 + 35 = 53
18 - 35 = -17
18 x 35 = 630
18 ÷ 35 = 0.5142857142857142
Using Variables in Calculations
You can also perform calculations on variables. The example below has the values of the variables pre-written.
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You need to store the result in a variable. The total variable has been used to store the result of the multiplication.
num1 = 12
num2 = 20
total = num1 * num2
print("The total is" , total)
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The total is 240
The example below allows the user to input values.
num1 = int(input("Enter number one: "))
num2 = int(input("Enter number two: "))
total = num1 + num2
print("The total is" , total)
Enter number one: 21
Enter number two: 82
The total is 103
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Don't leave the user in the dark, better user interfaces are clear and explain what outputted values mean:
num1 = int(input("Enter number one: "))
num2 = int(input("Enter number two: "))
answer = num1 - num2
print(num1 , "-" , num2 , "=" , answer)
Enter number one: 83
Enter number two: 29
83 - 29 = 54
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Simple Calculations Task 2 (Divide by 3)
Use an input line with int to ask the user to enter a number.
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Divide the number by 3 and output the result.
Example solution:
Enter a number: 11
11 divided by 3 is 3.6666666666666665
Simple Calculations Task 3 (Add 3 Numbers)
Make three input lines using int to ask the user to enter three numbers.
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Add the numbers together and output the total.
Example solution:
Enter the first number: 45
Enter the second number: 32
Enter the third number: 19
The total is 96