Class 7 Maths Chapter 3
Class 7 Maths chapter 3, In this chapter we learn about data collection, drawing a bar chart, mean, median, mode, range and probability.
In this chapter of class 7 we discuss about following topics, and the student can go directly by clicking by respective topics.Links are given below:
- NCERT Solutions for Class 7 Maths chapter 3 Exercise 3.1
- NCERT Solutions for Class 7 Maths chapter 3 Exercise 3.2
- NCERT Solutions for Class 7 Maths chapter 3 Exercise 3.3
- NCERT Solutions for Class 7 Maths chapter 3 Exercise 3.4
- Definitions of Mean, Median, Mode and Range
- Download PDF of Exercise 3.1, Exercise 3.2, Exercise 3.3 and Exercise 3.4
Solutions Exercise 3.1
Solutions Exercise 3.2
Solutions Exercise 3.3
Solutions Exercise 3.4
Question 1: Tell whether the following is certain to happen, impossible, can happen but not certain .
- (i) You are older today than yesterday.
- (ii) A tossed coin will land heads up.
- (iii) A die when tossed shall land up with 8 up.
- (iv) The next traffic light seen will be green .
- (v) Tomorrow will be a cloudy day.
Answer 1:
- (i) Certain
- (ii) Can happen
- (iii) Impossible
- (iv) Can happen
- (v) Can happen
- Question 2: There are 6 marbles in a box with numbers from 1 to 6 marked on each of them.
- (i) What is the probability of drawing a marble with number 2?
- (ii) What is the probability of drawing a marble with number 5?
(i) Total marbles = 6 (Total outcome) and number 2 have only one times (Favourable outcome)
Therefore, Probability = 1/6
(ii) Similarly, Probability = 1/6
Question 3: A coin is flipped to decide which team starts the game. What is the probability that your team will start?
Answer 3: Coin has two possible out come (i.e. head or tail) , But if head will occur , then my team will start.
Therefore Probability of my team =1/2
Definitions of Mean Median Mode
There are definitions of Class 7 Maths chapter 3, are given below :
ARITHMETIC MEAN:
The most common representative value of a group of data is called arithmetic mean or the mean.
Mean = (Sum of all observations)/(Number of observations)
Range:
The difference between the highest and the lowest observation gives us an idea of the spread of the observations.
This can be found by subtracting the lowest observation from the highest observation. We call the result the range of the observation. Look. In easy word Range is difference of highest observation and lowest observation.
Mode:
The mode of a set of observations is the observation that occurs most often. Means the observation that repeat maximum times in the given data is called mode.
Median:
In a given data, arranged in ascending or descending order, the median gives us the middle observation.
Some Related Information:
1. The collection, recording and presentation of data help us organise our experiences and draw inferences from them.
2. Before collecting data we need to know what we would use it for.
3. The data that is collected needs to be organised in a proper table, so that it becomes easy to understand and interpret.
4. Average is a number that represents or shows the central tendency of a group of observations or data.
5. Arithmetic mean is one of the representative values of data.
6. Mode is another form of central tendency or representative value. The mode of a set of observations is the observation that occurs most often.
7. Median is also a form of representative value. It refers to the value which lies in the middle of the data with half of the observations above it and the other half below it.
8. A bar graph is a representation of numbers using bars of uniform widths.
9. Class 7 Maths Chapter 3, you also learn about Double bar graphs which is helps us to compare two collections of data at a glance.
10. There are situations in our life, that are certain to happen, some that are impossible and some that may or may not happen. The situation that may or may not happen has a chance of happening.