Study the table and answer the following questions based on it. The following table gives the percentage of marks obtained by 7 students in 5 different subjects in an examination. (The maximum marks in a subject is 100.)Sub 1 Sub 2 Sub 3 Sub 4 Sub 5 Student 1 40 45 55 65 70 Student 2 60 70 75 65 60 Student 3 70 74 64 68 72 Student 4 50 75 57 65 62 Student 5 61 66 72 58 60 Student 6 70 65 68 56 78 Student 7 65 45 70 52 58
Find out the difference between the average marks in Subject 1 (Sub 1) and average marks in Subject 2 (Sub 2).
3.43
Calculating Average Marks Difference: Subject 1 vs Subject 2
This question asks us to find the difference between the average marks obtained in Subject 1 (Sub 1) and the average marks obtained in Subject 2 (Sub 2) based on the provided table showing the percentage of marks for 7 students in 5 subjects.
| Sub 1 | Sub 2 | Sub 3 | Sub 4 | Sub 5 | |
|---|---|---|---|---|---|
| Student 1 | 40 | 45 | 55 | 65 | 70 |
| Student 2 | 60 | 70 | 75 | 65 | 60 |
| Student 3 | 70 | 74 | 64 | 68 | 72 |
| Student 4 | 50 | 75 | 57 | 65 | 62 |
| Student 5 | 61 | 66 | 72 | 58 | 60 |
| Student 6 | 70 | 65 | 68 | 56 | 78 |
| Student 7 | 65 | 45 | 70 | 52 | 58 |
Step 1: Calculate the average marks for Subject 1 (Sub 1)
To find the average marks for Subject 1, we need to sum up the marks of all 7 students in Sub 1 and then divide by the total number of students, which is 7.
Marks in Subject 1 for all 7 students are: 40, 60, 70, 50, 61, 70, 65.
Sum of marks in Subject 1 = $40 + 60 + 70 + 50 + 61 + 70 + 65 = 416$
Average marks in Subject 1 = $\frac{\text{Sum of marks in Sub 1}}{\text{Number of students}} = \frac{416}{7}$
Average marks in Subject 1 $\approx 59.42857$
Step 2: Calculate the average marks for Subject 2 (Sub 2)
Similarly, to find the average marks for Subject 2, we sum up the marks of all 7 students in Sub 2 and divide by 7.
Marks in Subject 2 for all 7 students are: 45, 70, 74, 75, 66, 65, 45.
Sum of marks in Subject 2 = $45 + 70 + 74 + 75 + 66 + 65 + 45 = 440$
Average marks in Subject 2 = $\frac{\text{Sum of marks in Sub 2}}{\text{Number of students}} = \frac{440}{7}$
Average marks in Subject 2 $\approx 62.85714$
Step 3: Find the difference between the average marks
The question asks for the difference between the average marks in Subject 1 and average marks in Subject 2. We calculate the difference between the two average values we found in Step 1 and Step 2.
Difference = Average marks in Subject 2 - Average marks in Subject 1
Difference = $\frac{440}{7} - \frac{416}{7} = \frac{440 - 416}{7} = \frac{24}{7}$
Difference $\approx 3.42857$
Rounding the difference to two decimal places, we get 3.43.
Therefore, the difference between the average marks in Subject 1 and Subject 2 is approximately 3.43.
Revision Table: Data Interpretation Concepts
| Concept | Description | Formula Example |
|---|---|---|
| Average (Mean) | The sum of a set of values divided by the number of values. | Average $= \frac{\text{Sum of values}}{\text{Number of values}}$ |
| Data Interpretation | The process of analyzing and understanding data presented in tables, charts, or graphs to draw conclusions. | Involves calculations, comparisons, and analysis of trends or patterns. |
| Table Analysis | Extracting relevant information and performing calculations based on data organized in rows and columns. | Used to answer specific questions about the data set. |
Additional Information: Understanding Averages
The average, or arithmetic mean, is a fundamental concept used to represent a typical value in a set of numbers. When dealing with student marks in subjects, calculating the average helps us understand the overall performance level for a specific subject across all students or the overall performance of a single student across all subjects.
Key points about averages:
- It provides a single value that summarizes the entire dataset.
- It is sensitive to extreme values (outliers).
- Comparing averages of different sets (like subjects or students) allows for performance comparison.
- In this problem, comparing the average of Subject 1 and Subject 2 helps us see which subject had a generally higher score among this group of students.
The difference between the averages quantifies how much higher (or lower) one subject's performance was compared to another on average for the given set of students.
Important Questions from Tabulation
The table shows District-wise data of a number of primary school teachers posted in schools of a city.
Study the table and answer the question:
District
Male teachers
Female teachers
East
1650
2375
North
1075
2651
West
1280
1520
South
1170
1085
Central
690
859
What is the difference between the total number of male teachers in the districts East, North, West taken together and the total number of female teachers in the districts East and South?Table shows income (in Rs. ) received by 4 employees of a company during the month of December 2020 and all their income sources.
Source
Amit
Suresh
Nitin
Varun
Salary
35000
38500
29000
42000
Arrears
6000
6300
5000
7500
Bonus
1000
1100
1000
1240
Overtime
1800
1950
1400
1500
What is the ratio of salary of Varun to his income other than salary?Study the table and answer the question:
Income (Rs.)
No. of persons
Less than 200
12
Less than 250
26
Less than 300
34
Less than 350
40
Less than 400
50
What is the percentage of persons earning Rs. 250 or more?The following table shows the annual profit of a company (in Rs. lakh).
2014-2015
2015-2016
2016-0217
2017-2018
2018-2019
625
690
725
775
815
The period which has the maximum percentage increase in profit over the previous year is:
The table given below shows the number of persons participating in a survey from 6 different states.
States Persons S1 100 S2 200 S3 400 S4 500 S5 600 S6 800 What is the ratio of number of person participating in a survey from state S3 to the number of person participating in a survey from state S4?
