Quiz Discussion

In a set of three numbers, the average of first two numbers is 2, the average of the last two numbers is 3, and the average of the first and the last numbers is 4. What is the average of three numbers?

• 1] 2
• 2] 2.5
• 3] 3
• 4] 3.5

From a class of 42 boys, a boy aged 10 years goes away and in his place, a new boy is admitted. If on account of this change, the average age of the boys in that class increases by 2 months, the age of the newcomer is :

• 1] 19 years
• 2] 17 years
• 3] 10 years 6 months
• 4] 12 years 2 months

The average weight of 8 men is increased by 1.5 kg when one of the men, who weight 65 kg is replaced by a new man. The weight of the new man is-

• 1] 70 kg
• 2] 74 kg
• 3] 76 kg
• 4] 77 kg

The average of marks in Mathematics for 5 students was found to do 50. Later, it was discovered that in the case of one student the marks 48 were misread as 84. The correct average is :

• 1] 40.2
• 2] 40.8
• 3] 42.8
• 4] 48.2

In a family, the average age of a father and a mother is 35 years. The average age of the father, mother and their only son is 27 years. What is the age of the son?

• 1] 10 years
• 2] 10.5 years
• 3] 11 years
• 4] 12 years

The arithmetic mean of the scores of a group of students in a test was 52. The brightest 20% of them secured a mean score of 80 and the dullest 25% a mean score of 31. The mean score of remaining 55% is-

• 1] 45
• 2] 50
• 3] 51.4 approx
• 4] 54.6 approx

The average of 11 results is 60. If the average of first six results is 58 and that of last six is 63, find the 6th result-

• 1] 66
• 2] 55
• 3] 64
• 4] 68

A batsman makes a score of 270 runs in the 87th inning and thus increase his average by a certain number of runs that is a whole number. Find the possible values of the new average.

• 1] 98
• 2] 184
• 3] 12
• 4] All of these
• 5] None of these

The average of first five multiples of 3 is:

• 1] 9
• 2] 10
• 3] 8
• 4] 11

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