Quiz Discussion

The average age of P, Q and R is 15 years more than R's age. If the total age of P and Q together is 39 years, then R's age is ?

• 1] 12 years
• 2] 24 years
• 3] 16 years
• 4] 14 years

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 shop of electronic goods is closed on Monday. The average daily sales for remaining six days of a week is Rs. 15,640 and the average sale of Tuesday to Saturday is Rs. 14,124. The sales on Sunday is -

• 1] Rs. 20,188
• 2] Data inadequate
• 3] Rs. 23,220
• 4] Rs. 21,704

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%

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

Find the average increase rate, if increase in the population in the first year is 30% and that in the second year is 40%.

• 1] 41%
• 2] 56%
• 3] 40%
• 4] 38%
• 5] 39%

If the mean of a,b,c is M and ab+bc+ca=0, then the mean of a²,b²,c² is:

• 1]

  M²

• 2]

  3M²

• 3]

  6M²

• 4]

  9M²

The average temperature for the first four days of a week is 40.2° C and that of the last four days is 41.3° C. If the average temperature for the whole 40.6°C, then the temperature on the fourth day is-

• 1] 40.8° C
• 2] 41.3° C
• 3] 41.8° C
• 4] 38.5° C

The mean of 100 items was 46. Later on it was discovered that an item 16 was misread as 61 and another item 43 was misread as 34. It was also found that the number of item was 90 and not 100. Then what is the correct mean ?

• 1] 50
• 2] 50.7
• 3] 52
• 4] 52.7

Sachin Tendulkar has a certain average for 11 innings. In the 12th innings he scores 120 runs and thereby increases his average by 5 runs. His new average is :

• 1] 60
• 2] 62
• 3] 65
• 4] 66