The Farm Problem: Counting Animal Legs

1. The Challenge: Counting Legs on a Farm

A farmer asks you to count how many legs there are among all his animals. The farmer breeds three species: chickens (2 legs), cows (4 legs), and pigs (4 legs). Create a function animals(chickens, cows, pigs) that returns the total number of legs of all the animals.

2. Why It Matters

This challenge teaches weighted arithmetic calculations where different categories contribute different weights to a final total.

3. The Python Solution

Multiply each animal count by its leg multiplier and sum the results:

def animals(chickens, cows, pigs):
    return (chickens * 2) + (cows * 4) + (pigs * 4)

# Testing our function
print(animals(2, 3, 5)) # Output: 36 (4 + 12 + 20)
print(animals(1, 2, 3)) # Output: 22 (2 + 8 + 12)
print(animals(5, 2, 8)) # Output: 50 (10 + 8 + 32)

4. Formula Breakdown

• Chickens contribute chickens * 2 legs.
• Cows contribute cows * 4 legs.
• Pigs contribute pigs * 4 legs.

5. Common Mistakes

• Mismatched Argument Order: Passing arguments in the wrong order (e.g. animals(cows, chickens, pigs)) applies wrong leg multipliers to animals! Keep parameter order consistent.

6. Next Steps

Map parameter weights carefully. Next, let's check if a number is even or odd!