There are two Classes A and B having 25 and 30 students respectively. In Class-A the highest score is 21 and lowest score is 17. In Class-B the highest score is 30 and lowest score is 22. Four students are shifted from Class-A to Class-B. Consider the following statements: 1. The average score of Class-B will definitely decrease. 2. The average score of Class-A will definitely increase. Which of the above statements is/are correct?
1 only
Given:
| Class A | Class B | |
| Number of Students | 25 | 30 |
| Maximum marks | 21 | 17 |
| Minimum marks | 30 | 22 |
Concept:
The average will lie between the maximum and minimum score.
Average = \(\frac{Sum\ of\ individual\ scores}{Total\ number\ of\ students}\)
Calculation:
Average score of class B will lie between 22 and 30 and
Average score of class A will lie between 17 and 21.
Hence average score of Class B will be higher than that of class A students.
In case of class B overall average will definitely decrease as the students coming from class A have lower score than the average score of class
In case of class A we cannot say surely that average score will definitely increase as it will depend on the score of the 4 students who are shifting to class B.
Class A average score will decrease if top 4 scoring students from class A shifts to class B and if the bottom 4 scoring students shifts to class B then Class A average score will increase.
Hence, option 1 is correct.
Important Questions from Average
Average of 40 numbers is 71, if the number 100 replaced by 140, then average is increased by
The captain of a football team of 11 members is 28 years old and the goalkeeper is 4 years older than him. If the ages of these two are removed, then the average age of the remaining players is two years less than the average age of the whole team. What is the average age of the team?
The average weight of A, B, Cis 40 kg, the average weight of B, D, Eis 42 kg and the weight of Fis equal to that of B. What is the average weight of A, B, C, D, Eand F?
A cow costs more than 4 goats but less than 5 goats. If a goat costs between Rs. 600 and Rs. 800, which of the following is a most valid conclusion?
A student on her first 3 tests receives on an average score of N points. If she exceeds her previous average score by 20 points on her fourth test, then what is the average score for the first 4 tests?
