Question
The average of 20 numbers is 35. The average of first 11 numbers is 38 and that of the last 11 numbers is 32. If 10th number and 11th numbers are excluded, then what is the average of the remaining numbers?
Solution
Sum of 20 numbers = 20 × 35 = 700 Sum of 10th and 11th number = 38 × 11 + 32 × 11 – 700
= 70 × 11 – 700
= 770 – 700
= 70 Desired average = (700 – 70)/(20 – 2) = 35
More Average Questions
- There are 25 students in a class with an average age of 20 years. 5 more students join the class, reducing the average to 18 years. Find the average age of...
- Average weight of a group of ‘x’ people increased by 1.5 kg, when a person weighing 56 kg joined the group while the average weight increased by 2 kg when ...
- Average age of company A is 28 years and average age of both companies A and B is 20 years. If the ratio of number of employees in company A and B is 3:8, ...
- The average of three numbers P, Q and R is 1600. R is 75% more than P. The ratio of P and Q is 4:5 respectively. If R is 25% less than S, then find out the...
- The average of a group of observations is 34.4. If every observation is scaled by a factor of 2.5, what will the resulting average become?
- In a company, the average salary of 30 employees is ₹40,000. Out of these, the average salary of 20 employees is ₹35,000, and the average salary of 5 other...
- The average cost price of 13 pens (having equal cost price) decreased by Rs.3, when one of the pen is replaced by a new pen having cost price of Rs.60. Fin...
- In a class of ‘x’ students, if a new student weighing 32 kg joins the class, then the average weight of the class increases by 1 kg. If the new...
- In 25 matches, Nick had a bowling average of 10.4. After playing 2 more matches, where he took 2 wickets giving 52 runs, his average went up by 0.6. Determ...
- The average age of 22 children and their teacher's age are 20 years. If the teacher's age is excluded, the average reduces by 1. What is the teacher's age?
Relevant for Exams:
