PYTHON BASICS • LESSON 12

Conditional Statements — if, elif and else

Learn how Python makes decisions using conditions. You will work with if, elif, and else and apply them to real-world data analytics situations.

1. What is a Conditional Statement?

A conditional statement allows Python to make a decision based on whether a condition is True or False.

age = 20

if age >= 18:
    print("Adult")

Python checks the condition age >= 18. If it is True, the indented code runs.

2. The if Statement

The if statement executes a block of code only when its condition is True.

sales = 120000

if sales > 100000:
    print("Target achieved")

Notice the colon : after the condition and the indentation before print().

CHECK YOUR UNDERSTANDING

What happens when an if condition is False?

3. Predict the Output

marks = 75

if marks >= 50:
    print("Pass")

CHECK YOUR UNDERSTANDING

What will this program print?

4. The else Statement

Use else when you want Python to execute another block when the if condition is False.

marks = 42

if marks >= 50:
    print("Pass")
else:
    print("Fail")

CHECK YOUR UNDERSTANDING

What will be printed if marks = 42?

Fill in the Blank

Complete the statement: if age >= 18 ___

5. The elif Statement

Use elif when you need to check another condition after the previous condition was False.

marks = 82

if marks >= 90:
    print("Excellent")
elif marks >= 75:
    print("Very Good")
else:
    print("Keep Practicing")

CHECK YOUR UNDERSTANDING

What will the code print when marks = 82?

6. Multiple Conditions

Conditional statements become especially useful when combined with comparison and logical operators.

sales = 150000
profit = 30000

if sales >= 100000 and profit >= 25000:
    print("Strong Performance")
else:
    print("Review Performance")

CHECK YOUR UNDERSTANDING

What will this program print?

7. Nested if Statements

An if statement can be placed inside another if statement. This is called a nested conditional.

age = 25
has_id = True

if age >= 18:
    if has_id:
        print("Access Allowed")
    else:
        print("ID Required")
else:
    print("Underage")

CHECK YOUR UNDERSTANDING

What will the nested if example print?

8. Conditional Logic in Data Analytics

Analysts frequently use conditions to classify records, identify targets, flag unusual values, and create business categories.

revenue = 125000

if revenue >= 100000:
    status = "High"
else:
    status = "Low"

print(status)

Here, Python converts a numerical value into a business category.

CHECK YOUR UNDERSTANDING

Why are conditional statements useful in data analytics?

9. Predict the Output

revenue = 80000

if revenue >= 100000:
    print("High")
elif revenue >= 50000:
    print("Medium")
else:
    print("Low")

CHECK YOUR UNDERSTANDING

What will be printed?

10. Debugging Conditional Code

A common beginner mistake is forgetting the colon or using the assignment operator instead of a comparison operator.

score = 80

if score = 80:
    print("Good")

The condition should use ==, not =.

score = 80

if score == 80:
    print("Good")

CHECK YOUR UNDERSTANDING

Which operator should compare whether score is exactly 80?

11. Complete the Code

Fill in the Blank

Complete: if temperature > 30 ___

Fill in the Blank

Complete the comparison: if sales ___ 100000:

Fill in the Blank

Complete the alternative branch keyword: ___:

12. Practice Challenge

Suppose a company gives a bonus when an employee's sales are at least ₹100,000.

sales = 120000

if sales >= 100000:
    print("Bonus Eligible")
else:
    print("Not Eligible")

CHECK YOUR UNDERSTANDING

What will be printed?

13. Mini Challenge

Build a condition that classifies a customer's purchase:

₹50,000 or more → Premium
₹20,000 or more → Regular
Below ₹20,000 → Basic

purchase = 35000

if purchase >= 50000:
    category = "Premium"
elif purchase >= 20000:
    category = "Regular"
else:
    category = "Basic"

print(category)

CHECK YOUR UNDERSTANDING

What category will a purchase of ₹35,000 receive?

14. Final Challenge

A sales analyst wants to classify monthly performance:

Revenue ≥ ₹200,000 → Excellent
Revenue ≥ ₹100,000 → Good
Revenue ≥ ₹50,000 → Average
Otherwise → Needs Improvement

revenue = 135000

if revenue >= 200000:
    performance = "Excellent"
elif revenue >= 100000:
    performance = "Good"
elif revenue >= 50000:
    performance = "Average"
else:
    performance = "Needs Improvement"

print(performance)

CHECK YOUR UNDERSTANDING

What is the performance classification for revenue = ₹135,000?

Lesson 12 Recap

✓ if checks a condition.
✓ else handles the alternative.
✓ elif allows additional conditions.
✓ Conditions return True or False.
✓ and, or, and not can combine conditions.
✓ Conditional logic is widely used for data classification and business rules.
✓ Remember the difference between = and ==.

Next: Lesson 13 — for Loops