The average of 9 observations was 9, that of the 1st of 5 being 10 and that of the last 5 being 8. What was the 5th observation?

Related Mcqs:

1. The average of 18 observations was calculated and it was 124. Later on it was discovered that two observations 46 and 82 were incorrect. The correct values are 64 and 28. The correct average of 18 observations is___________?

   A. 123
   B. 137
   C. 121
   D. 122

2. The mean of 50 observations was 36. It was found later that an observation 48 was wrongly taken as 23. The corrected new mean is___________?

   A. 35.2
   B. 36.1
   C. 36.5
   D. 39.1

3. The average weight of 25 persons sitting in a boat had some value. A new person added to them whose weight was 46 kg only. Due to his arrival, the average weight of all the persons decreased by 5 kg. Find the average weight of first 25 persons?

   A. 55 kg
   B. 62 kg
   C. 56 kg
   D. None

4. The average runs scored by a batsman in 20 matches is 40. In the next 10 matches the batsman scored an average of 13 runs. Find his average in all the 30 matches?

   A. 31
   B. 29
   C. 28
   D. 30

5. The average age of seven persons sitting in a row facing east is 28 years. If the average age of the first three persons is 21 years and the average age of the last three persons is 34 years, then find the age of the person sitting in the middle of the row?

   A. 30 Years
   B. 31 years
   C. 26 years
   D. 33 years

6. The average mark of the students of a class in a particular exam is 80. If 5 students whose average mark in that exam is 40 are excluded, the average mark of the remaining will be 90. Find the number of students who wrote the exam.

   A. 20
   B. 15
   C. 25
   D. 35

7. The average monthly income of P and Q is Rs. 5050. The average monthly income of Q and R is 6250 and the average monthly income of P and R is Rs. 5200. The monthly income of P is____________?

   A. Rs. 3500
   B. Rs. 4000
   C. Rs. 4050
   D. Rs. 5000

8. A cricketer has a certain average for 10 innings. In the eleventh inning, he scored 108 runs, there by increasing his average by 6 runs. His new average is_____________?

   A. 48 runs
   B. 52 runs
   C. 55 runs
   D. 60 runs

9. The average of women and child workers in a factory was 15%yr. The average age of all the 16 children was 8yr and average age of women workers was 22 yrs if ten women workers were married then the number of unmarried women workers were________?

   A. 16
   B. 12
   C. 8
   D. 6

10. The average salary of all the workers in a workshop is Rs. 8000. The average salary of 7 technicians is Rs. 12000 and the average salary of the rest is Rs. 6000. The total number of workers in the workshop is__________________?

    A. 20
    B. 21
    C. 22
    D. 23