Introduction to Probability Exercise 7.1 Class 9 Maths Solutions

The Introduction to Probability Exercise 7.1 set opens the chapter with a single ranking task. It asks you to place everyday events on a likelihood scale. These NCERT Solutions Class 9 Maths Chapter 7 Introduction to Probability Exercise 7.1 explain each ranking in plain steps for the new Ganita Manjari book.

• Questions solved: 1 ranking question with four everyday events to judge.
• Main skill: placing an event on a scale from impossible to certain.
• Chapter link: it builds the words you will use in every later exercise.

These solutions are written by subject teachers, matched to the current 2026-27 NCERT book, and checked line by line so a Class 9 student can follow each reason.

What Does Class 9 Maths Chapter 7 Introduction to Probability Exercise 7.1 Cover?

This exercise teaches the language of chance before any formula. You learn that every event sits somewhere on a scale from 0 to 1. An event that can never happen has probability 0 and is called impossible. An event that must happen has probability 1 and is called certain. Between the two ends sit three more signposts: less likely, equally likely, and more likely. To rank an event you ask two things. Can it happen at all, and how strongly does experience say it will? This simple idea sets up the counting work that follows in Exercise 7.2 onward.

Video Walkthrough

Source: Magnet Brains on YouTube

Introduction to Probability Exercise 7.1 Question Breakdown

Exercise 7.1 has one question with four parts. Each part gives a real-life event, and you rank it and give a reason. The bullets below list what each part asks.

• Part (i): the next Monday coming after Sunday, a fixed weekly order.
• Part (ii): snow falling in Mumbai in July, a hot monsoon month.
• Part (iii): an elephant walking through your classroom today.
• Part (iv): greeting at least one friend at school tomorrow.

Sample Solved Question from Exercise 7.1

Here are two parts of the ranking question, solved with reasons, so you can see the method.

Question: Rank each event on a scale from 0 (impossible) to 1 (certain). (i) The next Monday will come after Sunday. (ii) It will snow in Mumbai in July.

Step 1. Read the scale. Impossible is P=0, certain is P=1, and an even chance is P=12.

Step 2. Judge part (i). In a normal week Sunday is always followed by Monday. There is no week where this fails, so the event is guaranteed and sits at the far right, P=1, certain.

Step 3. Judge part (ii). Mumbai is a warm coastal city, and July is its monsoon. Snow needs near-freezing air, which does not occur there, so the event sits at the far left, P=0, impossible.

Final answer. Part (i) is certain (P=1) and part (ii) is impossible (P=0).

How to Use These Introduction to Probability Exercise 7.1 Solutions

Read each event first and write your own ranking before you check ours. Then use these Collegedunia solutions to compare your reasons, not just your labels.

• Try to rank all four events yourself, then match your answers here.
• Focus on the reason, since a right label with a weak reason still loses marks.
• Learn the five signposts by heart before you move to Exercise 7.2.

More Class 9 Maths Introduction to Probability Solutions

Use the table below to open the full chapter or any other exercise of this chapter.