Bissoy.com
Doctors Medicines MCQs Q&A

The average marks of 60 students of a class were found to be 64. Later, it was found that marks of two students were wrongly read as 42 and 28 in place of 24 and 76 respectively. Then what is the correct average marks?

The average marks of 60 students of a class were found to be 64. Later, it was found that marks of two students were wrongly read as 42 and 28 in place of 24 and 76 respectively. Then what is the correct average marks? Correct Answer 64.5

Given:

Initially, average marks of 60 students = 64

Two marks were read wrongly as 42 and 28 instead of 24 and 76

Formula used:

Average of n numbers = Sum of all the numbers/n

Calculation:

Total marks of all students initially = 64 × 60 = 3840

Change in marks after correction = (24 + 76) - (42 + 28) = 30

Total correct marks = 3840 + 30 = 3870

∴ Correct average = 3870/60 = 64.5

Related Questions

The average marks obtained by 42 students of class A is 79 whereas, the average marks of 38 students of class B is 76. If marks of 5 students are removed who got minimum marks from class A, the average marks of class A is increased by 3 marks, then find the new average marks of class A and B.
Each question below is followed by two statements I and II. You have to determine whether the data given in the statements are sufficient for answering the question. You should use the data and your knowledge of Mathematics to choose the best possible answer. What is the average weight of new students added? I. In a class 60% students are male and there average weight is 15 kg more than the female students, 9 males and 6 new female students joined the class and the average weight of the class increased by 0.84 II. Total male students in the class is 12 more than female students adding 9 male students to the class increases the average weight of male students by 1 kg and adding 6 female students increases the average weight of female students by 0.6.
The average marks of 40 students of a class were 58. Later on, it was found that the marks of two students were wrongly read as 38 and 42 in place of 83 and 24. What are the CORRECT average marks?
The marks of 30 students in a test is shown as follows: 12, 16, 22, 24, 11, 7, 9, 11, 13, 14, 17, 19, 18, 21, 22, 23, 8, 9, 17, 16, 14, 23, 24, 24, 23, 17, 18, 16, 11, 9  Which Tally table represent the correct data of the marks of the students. (A) Interval of marks Tally marks of students 0-5 0 5-10 ||||  10-15 |||| || 15-20 |||| |||| 20-25 |||| ||||   (B)  Interval of marks Tally marks of students 0-5 0 5-10 |||| | 10-15 |||| ||| 15-20 |||| |||| 20-25 |||| || (C) Interval of marks Tally marks of students 0-5 0 5-10 |||| | 10-15 |||| || 15-20 |||| |||| 20-25 |||| || (D) Interval of marks Tally marks of students 0-5 0 5-10 ||||  10-15 |||| || 15-20 |||| ||| 20-25 |||| ||||
The average marks of the class were 60. When 12 students having average marks 65 left the class and 7 students having average marks 80 joined the class, then average marks of the class increased by 4 marks. The number of students, initially, in the class∶
In an examination, there were three subjects Hindi, Maths, and Science. Marks scored by Karan in Hindi is 60. Marks scored by Karan and Lokesh in Maths is equal. Marks scored in 3 subjects by Lokesh is 200. Marks scored by Lokesh in science is 25 % of total marks obtained. Marks scored by Mohit in Hindi is equal to marks scored by Lokesh in Maths. Marks scored in Maths by Mohit is 5 more than the marks scored in Hindi. Marks scored in Maths by Lokesh is 20 more than marks scored in Science. Marks obtained by Karan, Lokesh, and Mohit in Hindi are what percent of marks obtained by Karan, Lokesh, and Mohit in Maths?
The average marks of a class of 30 students are 52. One student whose marks are 82 left the class and two new students joined the class. The average of the class remains the same and the difference between the marks of new students is 4. What will be the marks of the student who scored greater marks between the two new students?
In the following question, two statements are numbered as A and B. On solving these statements we get quantities A and B respectively. Solve for the both quantities and choose the correct option. Quantity A: Vinay secured 92.5% marks in an examination comprising of 5 subjects each of 120 marks. He scored 95% marks in English and Hindi together, while 90% marks in Mathematics. In Science, if he scored one marks more than Social studies, how many marks did he scored in Science? Quantity B: Ashi scored 75%, 80% and 90% marks in Physics, Chemistry and Mathematics sections respectively, in an examination of total 150 marks. If the Physics and Chemistry sections are worth 40% and 20% of the total marks, how many marks did Ashi secured in the examination? 
In an examination, the difference of the highest and the least marks is 33. When the average of marks was taken without considering the highest marks then the average was reduced by 2% but when the average of marks was taken without considering the least marks then the average of the marks was increased by 3%. If there are 76 students, find the original average of the marks of all the students?
In a class of 60 students the average marks scored is 36, but later it was found out that marks of 2 student misread i.e noted 18 but instead the student got 32 marks and marks of one more student is noted as 20 but marks obtained by him is 12. What is the average marks of the class after correction is done?