The circumference of a circle is 2pr where r is the radius of the circle

 The circumference of a circle is 2pr where r is the radius of the circle. Write Python statements that calculate and print the circumference of a circle whose radius is 8 inches. Use a variable named radius and set it to 8. Use a variable named pi and set it to 3.14. Use a variable named circ that stores the calculated circumference using Python math operators. Output: The circumference of the circle is _____ inches.

The correct answer and explanation is :

Output:

The circumference of the circle is 50.24 inches.

Explanation (300+ words):

In this Python program, we are calculating the circumference of a circle using the mathematical formula:

[
\text{Circumference} = 2 \times \pi \times r
]

Where:

  • ( \pi ) (pi) is approximately 3.14
  • ( r ) is the radius of the circle
  • The result gives us the distance around the edge of the circle

Step-by-step Breakdown:

  1. Variable Declaration:
   radius = 8

This sets the radius of the circle to 8 inches. Variables are used to store data, and here radius is holding the numeric value 8.

  1. Assigning the value of pi:
   pi = 3.14

Although Python has a more accurate value of pi in its math module (math.pi), the problem specifies using 3.14, so we manually set it.

  1. Calculating Circumference:
   circ = 2 * pi * radius

This uses basic math operators:

  • * for multiplication
  • The expression follows the order of operations (PEMDAS)
  • First 2 * pi is computed (result: 6.28), then multiplied by the radius (8) So:
    [
    \text{circ} = 2 \times 3.14 \times 8 = 6.28 \times 8 = 50.24
    ]
  1. Printing the Result:
   print("The circumference of the circle is", circ, "inches.")

This prints the final value in a readable format. The print() function outputs text and variable values.


This program demonstrates how to use variables, apply mathematical formulas, and produce meaningful output — a key skill in both math and programming.

Would you like to see the same example using Python’s built-in math.pi for higher precision?

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