# Cl-5 (Math) | Ch-12 | Average

## Pre-Requisites

• Basic understanding

## Learning Objective

On successful completion of this lesson, students will be able to:

• demonstrate basic knowledge of average.
• analyze the concept to find average.
• develop problem-solving skills.
• apply in real life.

## Dictionary

• Average: Mean
• Numeral: Number
• >: Greater than
• <: Lesser than
• =: Equal to
• Ascending: Increasing
• Descending: Decreasing
• Order: Sequence

### 12.1 Introduction

#### Formula

To find average:

Average = Sum of all observations / Number of the observations

### 12.2 Characteristics of average

• It is a ratio.
• It gives an approx value.
• It is found to get an idea.
• It makes data to be remembered easily.
• It is used to analyse the data.

#### Solved Examples

Ex1. In a test, the marks obtained by Kajal are:

Find her average marks per subject.

Sol. We have:

Since, Sum of all the marks obtained= 90+85+80+75+70= 400

And, Number of the subjects= 5

Therefore , Average marks per subject = Sum of all marks obtained/ Number of the subjects

= 400/ 5

= 80

Thus, Kajal’s average marks per subject is 80.

Ex2. The daily earnings of a rickshaw puller during a week are:

Rs150, Rs140, Rs145, Rs130, Rs120, Rs90, Rs50. Find his average daily earning.

Sol. Total earnings = Rs(150+140+145+130+120+90+50)

Number of days = 7

Average earning per day = Rs825/7 =Rs117.85

Thus, his average daily earning is Rs117.85

Ex3. Find the average of the numbers 1, 2, 3, 4, 5.

Sol. Average = 1+2+3+4+5/5 = 15/5 = 3

Thus, tthe average of the given numbers is 3.

### 12.3 Practice Sets

1. Fill Type
2. Match Type
3. Order Type
4. Conversion Type
5. Compare Type
6. Error Type
7. Statement Type
8. True/False Type
9. Related Type
10. Day-to-Day Type
11. Miscellaneous Type

#### Set-1

1.Find the average.

2. Find the average of all odd numbers between

3. Which of the following are meaningless?

4. Compare and put symbol >, < or =in the placeholder.

5. Fill in the blanks.

6. Cross (x) the Roman numerals which are not written correctly.

7. Write the following Roman numerals in ascending order.

8. Write the following Roman numerals in descending order.

9. Solve & write the answer in Roman numerals.

10. Complete the following table.

Ans: 1 ( ), 2( ), 3( ), 4( ), 5( ), 6( ), 7( ), 8( ), 9( ), 10( )

#### Set-2

Ans: 1 ( ), 2( ), 3( ), 4( ), 5( ), 6( ), 7( ), 8( ), 9( ), 10( )

#### Set-3

Ans: 1 ( ), 2( ), 3( ), 4( ), 5( ), 6( ), 7( ), 8( ), 9( ), 10( )

#### Set-4

Ans: 1 ( ), 2( ), 3( ), 4( ), 5( ), 6( ), 7( ), 8( ), 9( ), 10( )

#### Set-5

Ans: 1 ( ), 2( ), 3( ), 4( ), 5( ), 6( ), 7( ), 8( ), 9( ), 10( )

Ans:

1. ..
2. ..
3. ..
4. ..
5. ….
6. ….
7. ….

### 12.6 Exam

The exam will be conducted after the completion of the course.