Check if Number is Less Than or Equal to Zero

Convert Minutes into Seconds

Learn how to convert minutes into seconds in Python using arithmetic multiplication and basic unit conversions.

1. The Challenge: Boolean Comparison

Create a function less_than_or_equal_to_zero(num) that takes a number as its only argument and returns True if it's less than or equal to zero, otherwise return False.

2. Why It Matters

Boolean comparison operators (<, <=, >, >=, ==, !=) are the decision-making engine behind conditional control flow in Python.

3. The Python Solution

Use the <= comparison operator, which returns a boolean True or False:

def less_than_or_equal_to_zero(num):
    return num <= 0

# Testing our function
print(less_than_or_equal_to_zero(5))  # Output: False
print(less_than_or_equal_to_zero(0))  # Output: True
print(less_than_or_equal_to_zero(-2)) # Output: True

4. Python Boolean Principles

In Python, booleans are capitalized: True and False (unlike JavaScript's lowercase true and false).

5. Common Mistakes

• Unnecessary If/Else Wrap: Writing if num <= 0: return True else: return False is redundant! The expression num <= 0 ALREADY evaluates directly to a boolean True or False. Return the expression directly!
• Confusing = with ==: Single = is for variable assignment. Double == or <= is for equality and comparison.

6. Next Steps

Return boolean expressions directly. Next, let's solve the Farm Problem animal legs challenge!