Quiz Discussion

The average of a group of men is increased by 5 years when a person aged of 18 years is replaced by a new person of aged 38 years. How many men are there in the group?

• 1] 3
• 2] 4
• 3] 5
• 4] 6
• 5] 7

The average of 50 numbers is 30. If two numbers, 35 and 40 are discarded, then the average of the remaining numbers is nearly:

• 1] 28.32
• 2] 29.68
• 3] 28.78
• 4] 29.27

The average age of a family of 10 members is 20 years. If the age of the youngest member of the family is 10 years, then the average age of the members of the family just before the birth of the youngest member was approximately.

• 1]

  27.14 years

• 2]

  12.5 years

• 3]

  14.28 years

• 4]

  \(11\frac{1}{9}\) years

The mean weight of 34 students of a school is 42 kg. If the weight of the teacher be included, the mean rises by 400 grams. Find the weight of the teacher (in kg.)

• 1] 55 kg
• 2] 57 kg
• 3] 66 kg
• 4] 56 kg

In a school with 600 students, the average age of the boys is 12 years and that of the girls is 11 years. If the average of the school is 11 years 9 months, then the average the number of girls in the school is :

• 1] 150
• 2] 250
• 3] 350
• 4] 450

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

Ajit has a certain average for 9 innings. In the tenth innings, he scores 100 runs thereby increasing his average by 8 runs. His new average is:

• 1] 20
• 2] 21
• 3] 28
• 4] 32

In Arun's opinion, his weight is greater than 65 kg but less than 72 kg. His brother doest not agree with Arun and he thinks that Arun's weight is greater than 60 kg but less than 70 kg. His mother's view is that his weight cannot be greater than 68 kg. If all are them are correct in their estimation, what is the average of different probable weights of Arun?

• 1]

  67 Kg

• 2]

  68 Kg

• 3]

  69 Kg

• 4]

  None Of These

Find the average of the following sets of scores:385, 441, 876, 221, 536, 46, 291, 428

• 1] 221
• 2] 403
• 3] 428
• 4] 536
• 5] None of these

The mean weight of 100 students in a class is 46 kg. The mean weight of boys is 50 and of girls is 40 kg. Therefore, the number of boys is:

• 1] 50
• 2] 60
• 3] 70
• 4] 65