Quiz Discussion

The average of 10 items was found to be 80 but while calculating, one of the items was counted as 60 instead of 50. Then the correct average would have been :

• 1] 69
• 2] 79.25
• 3] 79
• 4] 79.5

Students of three different classes appeared in common examination. Pass average of 10 students of first class was 70%, pass average of 15 students of second class was 60% and pass average of 25 students of third class was 80% then what will be the pass average of all students of three classes?

• 1] 74%
• 2] 75%
• 3] 69%
• 4] 72%

The average of the first five multiples of 3 is-

• 1] 3
• 2] 9
• 3] 12
• 4] 15

A librarian purchased 50 storybooks for his library. But he saw that he could get 14 books more by spending Rs. 76 more but per book average becomes Rs. 1 less. The average price (in Rs.) of each book he bought, was :

• 1] 15
• 2] 25
• 3] 20
• 4] 10

The average weight of 21 boys was recorded as 64 kg. If the weight of the teacher was added, the average increased by 1 kg. What was the teacher’s weight?

• 1] 86 kg
• 2] 64 kg
• 3] 72 kg
• 4] 84 kg

The speed of the train going from Nagpur to Allahabad is 100 km/h while when coming back from Allahabad to Nagpur, its speed is 150 km/h. find the average speed during whole journey.

• 1] 125 km/hr
• 2] 75 km/hr
• 3] 135 km/hr
• 4] 120 km/hr

David obtained 76, 65, 82, 67 and 85 marks (out of 100) in English, mathematics, physics, chemistry and biology. What are his average marks?

• 1] 65
• 2] 69
• 3] 75
• 4] None of these

The present age of a father is 3 years more than three times the age of his son. Three years hence, father's age will be 10 years more than twice the age of the son. The father's age is :

• 1] 33 years
• 2] 39 years
• 3] 45 years
• 4] 40 years

The average of nine number is 50. The average of first five numbers is 54 and that of the last three numbers is 52. Then the sixth number is :

• 1] 30
• 2] 34
• 3] 24
• 4] 44

Find the average of all the numbers between 6 and 34 which are divisible by 5 -

• 1] 18
• 2] 20
• 3] 24
• 4] 30