Directions (1 to 5): In a school the periodical examination are held every second month. In a session during April 2001 - March 2002, a student of Class IX appeared for each of the periodical exams. The aggregate marks obtained by him in each perodical exam are represented in the line-graph given below.
Marks Obtained by student in Six Periodical Held in Every Two Months During the Year in the Session 2001 - 2002.
Maximum Total Marks in each Periodical Exam = 500
1. In which periodical exams did the student obtain the highest percentage increase in marks over the previous periodical exams ?
A. June, 01
B. August, 01
C. October, 01
D. December, 01
2. The total number of marks obtained in Feb. 02 is what percent of the total marks obtained in April 01 ?
A. 110%
B. 112.5%
C. 115%
D. 116.5%
3. What is the percentage of marks obtained by the student in the periodical exams of August, 01 and Oct, 01 taken together ?
A. 73.25%
B. 75.5%
C. 77%
D. 78.75%
4. What are the average marks obtained by the student in all the periodical exams during the last session ?
A. 373
B. 379
C. 381
D. 385
5. In which periodical exams there is a fall in percentage of marks as compared to the previous periodical exams ?
A. None
B. June, 01
C. Oct, 01
D. Feb, 02
Answers and Explanations
1. Answer - Option C
Explanation -
Percentage increase in marks in various periodical exams compared to the previous exams are:
For Jun 01 = [latex][\frac {(365 - 360)}{360} \times 100][/latex] % = 1.39%.
For Aug 01 = [latex][\frac {(370 - 365)}{365} \times 100][/latex] % = 1.37%.
For Oct 01 = [latex][\frac {(385 - 370)}{370} \times 100][/latex] % = 4.05%.
For Dec 01 = [latex][\frac {(400 - 385)}{385} \times 100][/latex] % = 3.90%.
For Feb 02 = [latex][\frac {(404 - 400)}{400} \times 100][/latex] % = 1.25%.
Clearly, highest percentage increase in marks is in Oct 01.
2. Answer - Option B
Explanation -
Here it is clear from the graph that the student obtained 360, 365, 370, 385, 400 and 405 marks in periodical exams held in Apr 01, Jun 01, Aug 01, Oct 01, Dec 01 and Feb 02 respectively.
Required percentage =[latex](\frac {405}{360} \times 100)[/latex]% = 112.5%.
3. Answer - Option B
Explanation -
Required percentage =[latex][\frac {(370 + 385)}{(500 + 500)} \times 100][/latex]% = [latex]\frac {(755 x 100)}{1000}[/latex]% = 75.5%.
4. Answer - Option C
Explanation -
Average marks obtained in all the periodical exams
=[latex]\frac {1}{6} \times [360 + 365 + 370 + 385 + 400 + 405][/latex] = 380.83 ≈ 381.
5. Answer - Option A
Explanation -
As is clear from the graph, the total marks obtained in periodical exams, go on increasing. Since, the maximum marks for all the periodical exams are the same; it implies that the percentage of marks also goes on increasing.
Thus, in none of the periodical exams, there is a fall in percentage of marks compared to the previous exam.