# Complete Python Practice Set with Answers

## **1. Variables and Naming Conventions**

**Questions**

### 1. Which of the following are valid Python variable names?

a) my_var
b) 2var
c) _name
d) var-name
e) Var123

### 2. Create 3 variables to store your **name**, **age**, and **grade**. Print them in one line.

### 3. Create a constant `PI = 3.14159` and print it.

**Answers**

# Valid names: my_var, _name, Var123
name = "Alice"
age = 20
grade = "A"
print(name, age, grade)

PI = 3.14159
print(PI)

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## **2. Data Types**

**Questions**
### 4. Assign values: 25, 3.14, True, "Python" to variables and print their types.
### 5. Swap values of `a = 5` and `b = 10` without using a temporary variable.

### **Answers**

x = 25
y = 3.14
z = True
s = "Python"

print(type(x))  # int
print(type(y))  # float
print(type(z))  # bool
print(type(s))  # str

a, b = 5, 10
a, b = b, a
print(a, b)  # 10 5

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## **3. Type Casting**

### **Questions**
### 6. Convert `"456"` to int and add 10.
### 7. Convert float `9.87` to int.
### 8. Take a number input from user, convert to float, multiply by 3.

**Answers**

print(int("456") + 10)  # 466
print(int(9.87))        # 9

x = float(input("Enter number: "))
print(x * 3)

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## **4. Strings and String Slicing**

### **Questions**
### 9. `text = "PythonProgramming"`. Print:

* First 6 characters
* Last 6 characters
* Characters from index 2 to 8
* Every 2nd character
* Reverse the string

### 10. Take first and last name input and print full name in uppercase.

### 11. Use f-string to print `"Hello, <name>! You are <age> years old."`

### **Answers**

text = "PythonProgramming"
print(text[:6])    # Python
print(text[-6:])   # mming
print(text[2:9])   # thonPro
print(text[::2])   # Pto rgamn
print(text[::-1])  # gnimmargorPmhtyP

first = input("First name: ")
last = input("Last name: ")
print((first + " " + last).upper())

name = "Alice"
age = 20
print(f"Hello, {name}! You are {age} years old.")

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## **5. Lists**

### **Questions**
### 12. Create a list of 5 numbers.
### 13. Add a number.
### 14. Remove the third number.
### 15. Print list reversed.
### 16. Find max and min.
### 17. Count occurrences of a number.
### 18. Sort ascending and descending.

### **Answers**

numbers = [10, 20, 30, 40, 50]
numbers.append(60)
numbers.pop(2)
print(numbers[::-1])
print(max(numbers), min(numbers))
print(numbers.count(20))
numbers.sort()
print(numbers)
numbers.sort(reverse=True)
print(numbers)

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## **6. Tuples**

**Questions**
### 19. Create a tuple of 5 numbers.
### 20. Try changing the second number. What happens?
### 21. Print length and max value.

### **Answers**

t = (1, 2, 3, 4, 5)
# t[1] = 10  # Error: tuples are immutable
print(len(t))
print(max(t))

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## **7. Sets**

### **Questions**
### 22. Create a set of 5 colors.
### 23. Add a new color.
### 24. Remove a color.
### 25. Try adding duplicate.

### **Answers**

colors = {"red", "blue", "green", "yellow", "black"}
colors.add("white")
colors.remove("blue")
colors.add("red")  # no effect
print(colors)

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## **8. Dictionaries and CRUD with Input**

**Questions**
### 26. Create a dictionary: `{"name": ..., "age": ..., "grade": ...}`
### 27. Add a `"school"` key.
### 28. Update `"grade"` to `"A+"`.
### 29. Delete `"age"` key.
### 30. Print keys, values, items.
### 31. Check if `"name"` exists.
### 32. Merge `{"hobby": "Reading"}`.
### 33. Take **input from user** for student name, age, grade, add to dictionary.

### **Answers**

student = {"name": "Alice", "age": 20, "grade": "A"}
student["school"] = "XYZ School"
student["grade"] = "A+"
del student["age"]
print(student.keys())
print(student.values())
print(student.items())
print("name" in student)
student.update({"hobby":"Reading"})
print(student)

# Input from user
name = input("Name: ")
age = int(input("Age: "))
grade = input("Grade: ")
student = {"name": name, "age": age, "grade": grade}
print(student)

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## **9. If-Else**

**Questions**
### 34. Number input → Positive, Negative, Zero
### 35. Check even/odd
### 36. Score input → Grade A,B,C,F

### **Answers**

num = int(input("Enter number: "))
if num > 0: print("Positive")
elif num < 0: print("Negative")
else: print("Zero")

if num % 2 == 0: print("Even")
else: print("Odd")

score = int(input("Enter score: "))
if score >= 90: print("A")
elif score >= 75: print("B")
elif score >= 50: print("C")
else: print("F")

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## **10. Loops (Extra)**

### **Questions**
### 37. Print 1–10 (for loop)
### 38. Print even numbers 1–20 (while loop)
### 39. Sum first 20 natural numbers
### 40. Multiplication table of a number
### 41. Print all items of a list using a loop
### 42. Nested loop: print a 5×5 star pattern
### 43. Loop through dictionary items and print key-value pairs
### 44. Take multiple student names as input (5 names) and store in a list using loop

### **Answers**

# For loop
for i in range(1,11): print(i)

# While loop
i = 2
while i <= 20:
    print(i)
    i += 2

# Sum
total = sum(range(1,21))
print(total)

# Multiplication table
n = int(input("Enter number: "))
for i in range(1,11):
    print(f"{n} * {i} = {n*i}")

# List loop
lst = [10,20,30]
for item in lst: print(item)

# Nested loop (star pattern)
for i in range(5):
    for j in range(5):
        print("*", end=" ")
    print()

# Dictionary loop
student = {"name":"Alice","grade":"A"}
for key, value in student.items():
    print(key, ":", value)

# Input multiple names
names = []
for i in range(5):
    name = input(f"Enter name {i+1}: ")
    names.append(name)
print(names)

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## **11. Functions**

**Questions**
### 45. `greet(name)` prints greeting
### 46. `is_even(num)` → True/False
### 47. `factorial(n)` returns factorial
### 48. `reverse_string(s)` → reversed string
### 49. `sum_of_list(lst)` → sum
### 50. `max_min(lst)` → max and min
### 51. `count_vowels(s)` → number of vowels
### 52. `is_prime(n)` → True/False
### 53. `find_occurrences(lst,x)` → number of times x occurs

### **Answers**

def greet(name): 
    print(f"Hello, {name}!")
    
def is_even(num): 
    return num%2==0

def reverse_string(s): 
    return s[::-1]

def sum_of_list(lst): 
    return sum(lst)
def max_min(lst): 
    return max(lst), min(lst)
def count_vowels(s): 
    return sum(1 for c in s if c in "aeiouAEIOU")
def is_prime(n):
    if n<2: return False
    for i in range(2,int(n**0.5)+1):
        if n%i==0: return False
    return True

def find_occurrences(lst,x): 
    return lst.count(x)

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## **12. Mini Projects**

**Shopping List Manager**

shopping_list=[]
for i in range(5):
    shopping_list.append(input("Enter item: ").upper())
print(shopping_list)

**Simple Calculator**

def calculate(a,b,op):
    if op=="+": return a+b
    elif op=="-": return a-b
    elif op=="*": return a*b
    elif op=="/": return a/b
    else: return "Invalid operation"

a=float(input("Enter first number: "))
b=float(input("Enter second number: "))
op=input("Enter operation (+,-,*,/): ")
print("Result:", calculate(a,b,op))

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