Python practice 2

Topics Covered: Variables, Expressions, Statements, Input, Type Conversion, Syntax Handling

Q1. Simple Calculation with Type Conversion

Ask user for hours and rate, calculate gross pay
Handle invalid input using try/except

hours = input("Enter Hours: ")  
rate = input("Enter Rate: ") 

try:
    hours = float(hours) 
    rate = float(rate) 
    pay = hours * rate 
    print("Gross Pay:", pay)  
except:
    print("⚠ Error: Please enter numeric value")  

Gross Pay: 25.0

105.0

 try:
    (hours,rate) = map(float,[input("Enter hours"),input("Enter rate")])
    
    print(hours*rate)
 except ValueError:
      print("Error:Please enter numeric value")

10.0

try:
    (hours,rate) = map(float,input( "Enter hours and rate separated by space").split())
    print(hours*rate)
except ValueError:
    print("⚠ Error: Please enter two numeric values separated by space")     

⚠ Error: Please enter two numeric values separated by space

Q2. Identify and Correct the Bug

This code has an error — fix it

TODO: Fix and explain what was wrong

In this code Pay = string & 2*Rate = Numeric value & In python we can't add string & numeric value.

 print("Pay:" +2 *rate)     # ❌ Buggy line

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
Cell In[84], line 1
----> 1 print("Pay:" +2 *rate)

TypeError: can only concatenate str (not "int") to str

We can use , or * between string & numeric values

rate = 10
print("Pay:" ,2 *rate)
print("Pay:" *2 *rate)

Pay: 20
Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:Pay:

f-strings make it easy to build dynamic text by embedding variables or expressions directly into a string using {}

f-strings(formatted strings)

rate = 2.5
print(f"Pay:{2 * rate}")

Pay:5.0

rate = 50
print(f"Square of rate: {rate**2}, Double: {2 * rate}")

Square of rate: 2500, Double: 100

Q3. Predict the Output

What will this print?

x = 5
x = x + 2
print(x)  # 👉 Your prediction: 7

7

Q4. Debugging Practice

Identify and fix 2 problems in this code

# name = input("Enter your name")
# print("Hello" name)  # Syntax Error

# Fixed:
name = input("Enter your name: ")
print("Hello", name)

Hello Lara

Q5. Multiple Variable Assignments

Swap values of two variables without using a third variable

a = 10
b = 20

# TODO: Swap the values
#  After swap, a = 20, b = 10
print(f"a: {a}, b: {b}")

a: 10, b: 20

Q6. Advanced Input Parsing

inp = input("Enter Hours & rate separated by space: ") 
Hours,rate = inp.split()
Hours = float(Hours)
rate = float(rate) 
pay = Hours * rate
print("pay:", pay)

pay: 8.0

try:
    hours,rate = map(float,[input("Enter hours: "),input("Enter rate: ")])
    print(hours*rate)
except ValueError:
    print("Error!: Please Enter numeric value only.")

10.0

hours,rate = map(float,input("Enter hours and rate separated by space: ").split())
pay = hours * rate
print(pay)

40.0

try:
    hours,rate = map(float,input("Enter hours and rate separated by space: ").split())
    print(hours*rate)
except ValueError:
    print("Error!: Enter pair of numeric values separated by space only!")

14.4825

Pencils,Rate = map(float,input("Enter Pencils and Rate per pencil separated by space").split())
print(Pencils*Rate) 
  

50.0

try:
    Pencils,Rate = map(float,[input("Enter no. of Pencils: "),input("Enter Rate: ")])
    print(Pencils*Rate)
except ValueError:
    print("Error!: Please enter numeric value only!")
    

32.0

Q7. Check Types and Do Arithmetic

x = float(input("Enter a number: "))
print("Before conversion:", type(x))
x = float(x)
print("Square:", x ** 2) 

Before conversion: <class 'float'>
Square: 25.0

try:
    x = float(input("Enter value of x: "))
    print(f"Before conversion: {type(x)}")
    print(f"Square: {x**2}")
except ValueError:
    print("Error!: Please enter numeric value only!")

Error!: Please enter numeric value only!

Q8. Dynamic Message Generator

name = input("Enter your name: ")
subject = input("Enter subject: ")
print(f"Hello {name}, welcome to {subject}!")

Hello Lara, welcome to Python programming!

Q9. Complex Expression Evaluation

expr = 10 + 5 * 2 - 3 / 2
print("Result:", expr)   #  Because of operator precedence: *, / first then +, -

Result: 18.5

Q10. Mini Project: Simple Tip Calculator

bill = float(input("Enter bill amount: "))
tip_percent = float(input("Enter tip %: "))
people = int(input("Split between how many people?"))

tip = bill * (tip_percent/100)
total = bill + tip
per_person = total/people

print("Tip amount:" , round(tip,2))
print("Total per person:" , round(per_person,2))

Tip amount: 25.0
Total per person: 131.25

try:
    bill,tip_percent = map(float,[input("Enter bill amount: "), input("Enter tip %: ")])
    people = int(input("Split between how many people?"))

    tip = bill*(tip_percent/100)
    total = bill + tip
    per_person = total/people

    print("Tip amount:", round(tip,2))
    print("Total per person:", round(per_person,2)) 
except ValueError:
    print("Error: Please enter integer value for people!")

Tip amount: 50.0
Total per person: 105.0