Quiz Discussion

Average of a, b, and c is 11; average of c, d and e is 17; average of e and f is 22 and average of e and c is 17. Find out the average of a, b, c, d, e and f.

• 1]

  \(15\frac{2}{3}\)

• 2]

  \(18\frac{1}{2}\)

• 3]

  \(16\frac{1}{2}\)

• 4]

  None of these

If the average of x and 1/x(X\( \ne \)0) is M, then the average of x2 and 1/x² is :

• 1] 1 - M2
• 2] 1 - 2M2
• 3] 2M2 - 1
• 4] 2M2 + 1

The average marks of four subjects is 120. If 33 was misread as 13 during the calculation, what will be the correct average?

• 1] 122
• 2] 120
• 3] 125
• 4] 121

40% of the employees in a factory are workers. All the remaining employees are executives. The annual income of each worker is Rs. 390. The annual income of each executive is Rs. 420. What is the average annual income of all the employees in the factory together?

• 1] 390
• 2] 405
• 3] 408
• 4] 415

The average of first five multiples of 3 is:

• 1] 9
• 2] 10
• 3] 8
• 4] 11

Average weight of 25 students of a class is 50 kg. If the weight of the class teacher is included , the average is increased by 1 kg. The weight of the teacher is ?

• 1] 76 kg
• 2] 77 kg
• 3] 74 kg
• 4] 75 kg

The average age of 3 children in a family is 20% of the average age of the father and the eldest child. The total age of the mother and the youngest child is 39 years. If the father's age is 26 years, what is the age of the second child ?

• 1] 15 years
• 2] 18 years
• 3] 20 years
• 4] Cannot be determined

The average weight of a group of 75 girls was calculated as 47 kgs. It was later discovered that the weight of one of the girls was read as 45 kgs. Whereas her actual weight was 25 kgs. What is the actual average weight of the group of 75 girls? ( Rounded off to two digits after decimal).

• 1] 34
• 2] 36
• 3] 30
• 4] None of these

There were 35 students in a hostel. Due to the admission of 7 new students the expenses of the mess were increased by Rs.42 per day while the average expenditure per head diminished by Re 1. What was the original expenditure of the mess?

• 1] Rs. 450
• 2] Rs. 320
• 3] Rs. 550
• 4] Rs. 420

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