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Hillary Nartey
Hillary Nartey

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# Day 2: Variables, Data Types & Conditionals in Python — With a Real Project!

#ai #python #beginners

By Hillary Nartey | AI Data Specialist in Training

Welcome Back!

This is Day 2 of my Python learning journey. If you missed Day 1, I shared how I got started, the free tools I am using, and why I chose Python as my first programming language.

Today I covered three important Python basics:

  • Variables
  • Data Types
  • Conditionals (if, elif, else)

And the best part? I built a small real-world project to practice everything together!

Variables

A variable is simply a container that stores a value. Think of it like a labeled box where you keep information.

name = "Hillary"
age = 25
price = 9.99
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Each of these is a variable. name stores text, age stores a whole number, and price stores a decimal number.

Data Types

In Python, every value has a data type. Here are the basic ones I learned today:

Data Type Example Description
int 25 Whole numbers
float 9.99 Decimal numbers
str "Hillary" Text (string)
bool True / False Yes or No values

You can also tell Python exactly what type a variable should be. For example:

amount: int = int(input("Enter your shopping amount: "))
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Here I am telling Python that amount should be an integer, and I am converting the user's input into one using int().

Conditionals (if, elif, else)

Conditionals let your program make decisions. It checks a condition and runs different code depending on whether it is TRUE or FALSE.

The basic structure looks like this:

if condition:
    # do this
elif another_condition:
    # do this instead
else:
    # do this if nothing above is true
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My Mini Project: Shopping Discount Calculator 🛒

To practice everything I learned today, I built a simple shopping discount calculator. It takes the amount a customer spends and automatically calculates their discount and final price.

amount: int = int(input("Enter your shopping amount: "))

if amount < 50:
    discount = 0
    print("No discount")
elif amount >= 50 and amount <= 99:
    discount = 0.10
    print("You have 10% discount")
elif amount >= 100 and amount <= 199:
    discount = 0.20
    print("You have 20% discount")
else:
    discount = 0.30
    print("You have 30% discount")

final = amount * (1 - discount)

if final > 150:
    print("You are a big spender")
else:
    print("Great deal")

print(f"Your final price is: ${final}")
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How it works:

  • The user enters how much they are spending
  • The program checks which discount range they fall into
  • It calculates the final price after the discount
  • It also checks if the final amount makes them a "big spender."

For example, if you enter $120:

  • You get a 20% discount
  • Your final price becomes $96.00
  • And you get a "Great deal" message!

What I Learned From This Project

Building this small project taught me more than just reading about variables and conditionals. I learned how to:

  • Take user input with input()
  • Convert data types using int()
  • Use multiple conditions with elif
  • Combine conditions using and.
  • Calculate values using arithmetic operators
  • Display results using f-strings like f"Your final price is: ${final}".

Key Takeaways from Day 2

  • Variables store information that your program can use
  • Data types tell Python what kind of information is being stored
  • Conditionals allow your program to make decisions
  • The best way to learn is to build something — even something small!

What's Coming on Day 3?

Next, I plan to cover:

  • Lists — storing multiple values in one variable
  • Loops — repeating actions automatically
  • Another small project to practice!

Thanks for following along! If you are also a beginner, drop a comment below — let's learn together! 🚀

Written by Hillary Nartey | AI Data Specialist in Training

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