Quiz Discussion

The average age of a class is 15.8 years. The average age of the boys in the class is 16.4 years while that of the girls is 15.4 years. What is the ratio of boys to girls in the class?

• 1]

  1:2

• 2]

  2:3

• 3]

  3:4

• 4]

  3:5

The average of 11 players of a cricket team is decreased by 2 months when two of them aged 17 years and 20 years are replaced by two new players. The average age of the new players is-

• 1] 17 years 1 month
• 2] 17 years 7 months
• 3] 17 years 11 months
• 4] 18 years 3 months

In a boat there are 8 men whose average weight is increased by 1 kg when 1 man of 60 kg is replaced by a new man. What is weight of new comer?

• 1] 70 kg
• 2] 66 kg
• 3] 68 kg
• 4] 69 kg

Out of 9 persons, 8 persons spent Rs. 30 on each of their meals. The ninth one spends Rs. 20 more than the average expenditure of all the nine. The total money spent by all of them was

• 1]

  Rs 260

• 2]

  Rs 290

• 3]

  Rs 292.5

• 4]

  Rs 400.5

The average age of 30 students is 9 years. If the age of their teacher is included, the average age becomes 10 years. The age of the teacher (in years) is :

• 1] 27
• 2] 31
• 3] 35
• 4] 40

The average age of 40 students of class is 18 years. When 20 new students are admitted to the same class, the average age of the students of the class is increased by 6 months. The average age of newly admitted students is ?

• 1] 19 years
• 2] 19 years 6 months
• 3] 20 years
• 4] 20 years 6 months

A cricketer has a certain average for 9 innings, In the tenth inning he scores 100 runs there by increasing his average by 8 runs. His new average is 

• 1]

  28 runs

• 2]

  24 runs

• 3]

  32 runs

• 4]

  20 runs

The mean of 100 observations was calculated as 40. It was founder later on that one of the observation was misread as 83 instead of 53. The correct mean is :

• 1] 39
• 2] 39.7
• 3] 40.3
• 4] 42.7

A batsman makes a score of 87 runs in the 17th inning and thus increases his average by 3. Find his average after 17th inning.

• 1] 40
• 2] 39
• 3] 52
• 4] 55

The average monthly salary of 660 workers in a factory is Rs. 380. The average monthly salary of officers is Rs. 2100 and the average monthly salary of the other workers is Rs. 340. Find the number of other workers.

• 1] 645
• 2] 650
• 3] 640
• 4] 642