Numbers

On This Page

• 4.1  Integers
• 4.2  Float
• 4.3  Complex Numbers
• 4.4  Type Conversion
• 4.5  Mathematical Functions
• 4.6  The Math Module
• 4.7  Practical Exercises
• 4.8  Module Quiz (MCQs)
• 4.9  Module Assignment
• 4.10  Interview Questions — Module 4
• 4.11  Student Notes Page

Module 4: Numbers

4.1  Integers

An integer (int) is a whole number — positive, negative, or zero — with no decimal point. Python integers have no fixed size limit, unlike many other languages.

students = 45
batches = -2       # negative integers are valid
big_number = 123456789012345
print(students, batches, big_number)
print(type(students))

4.2  Float

A float represents a number with a decimal point, used for prices, percentages, measurements, and any value requiring precision.

course_fee = 15000.50
gst_rate = 0.18
pi_value = 3.14159
print(course_fee, gst_rate, pi_value)
print(type(course_fee))

4.3  Complex Numbers

Python also supports complex numbers, written as a + bj, where 'j' represents the imaginary part. These are rarely used in business analytics but are common in scientific and engineering computing.

z = 3 + 4j
print(z)
print(z.real)   # real part
print(z.imag)   # imaginary part
print(type(z))

4.4  Type Conversion

You can convert freely between int, float, and complex using built-in functions.

4.5  Mathematical Functions

Python has several built-in functions for common numeric operations — no import needed.

marks = [78, 85, 92, 66, 88]
print("Highest:", max(marks))
print("Lowest:", min(marks))
print("Total:", sum(marks))
print("Average:", round(sum(marks)/len(marks), 2))

4.6  The Math Module

For advanced mathematical operations (square roots, logarithms, trigonometry), Python provides the built-in math module, which must be imported first.

import math

print(math.sqrt(64))       # square root
print(math.ceil(4.2))      # round UP
print(math.floor(4.8))     # round DOWN
print(math.factorial(5))   # 5! = 120
print(math.pi)             # value of pi

4.7  Practical Exercises

Basic (5 Questions)

1. Store your age as an integer and your height (in meters) as a float, then print both.

2. Use abs() to print the absolute value of -45.

3. Round the number 7.6789 to 2 decimal places.

4. Find the maximum and minimum of 5 numbers using max() and min().

5. Import the math module and print the value of pi.

Intermediate (5 Questions)

1. Calculate the average of 6 student marks stored in a list using sum() and len().

2. Use math.sqrt() to find the square root of a number entered by the user.

3. Compare math.ceil() and math.floor() on the number 6.3 and explain the difference.

4. Write a program to calculate compound interest using pow().

5. Create a program that converts a float course fee into an integer and explains what is lost.

Advanced (5 Questions)

1. Build a 'Marks Analyzer': given a list of marks, print the highest, lowest, total, and average.

2. Write a program to calculate the EMI-style monthly payment using basic math functions.

3. Explain why 0.1 + 0.2 does not exactly equal 0.3 in Python, with a code demonstration.

4. Use math.factorial() to calculate the number of ways to arrange 6 students in a row.

5. Create a GST Calculator that takes a price, applies 18% GST, and rounds the final amount to 2 decimals.

4.8  Module Quiz (MCQs)

4.9  Module Assignment

Assignment: Course Fee & GST Calculator

• Take the base course fee as input (float).
• Calculate 18% GST on it using an expression.
• Add GST to the base fee to get the final payable amount.
• Round the final amount to 2 decimal places and print a clean summary using an f-string.

Expected Output: A script that correctly computes GST-inclusive course fees and displays a clean, rounded final amount — usable as a real billing helper for the institute.

4.10  Interview Questions — Module 4

• Q: What is the difference between int and float in Python?
  A: int stores whole numbers with no decimal point, while float stores numbers with decimal precision.
• Q: Why might 0.1 + 0.2 not equal exactly 0.3 in Python?
  A: Floats are stored in binary format which cannot represent some decimal fractions exactly, causing tiny rounding errors.
• Q: What is the difference between round(), math.floor(), and math.ceil()?
  A: round() rounds to the nearest value, math.floor() always rounds down, and math.ceil() always rounds up, regardless of the decimal value.
• Q: Do you need to import anything to use abs() or round()?
  A: No — abs(), round(), max(), min(), and sum() are built-in functions available without any import, unlike sqrt() or factorial() which require the math module.

4.11  Student Notes Page

Use this space to write down key points, doubts, and your own examples from today's session.