Quiz Discussion

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

The average of six number is x and the average of three of these is y. the average of the remaining three is z, then 

• 1]

  x=y+z

• 2]

  2x=y+z

• 3]

  x=2y+2z

• 4]

  x=2yz

A cricketer whose bowling average is 12.4 runs per wicket takes 5 wickets for 26 runs and thereby decreased his average by 0.4. The number of wickets taken by him the last match was-

• 1] 64
• 2] 72
• 3] 80
• 4] 85

10 years ago, the average age of a family of 4 members was 24 years. Two children having been born (with age difference of 2 years), the present average age of the family is again 24 years. Then the present age of the youngest child is:

• 1]

  1 years

• 2]

  2 years

• 3]

  3 years

• 4]

  4 years

30 pens and 75 pencils altogether were purchased for Rs. 510. If the average price of a pencil was Rs. 2, what was the average price of a pen ?

• 1] Rs. 9
• 2] Rs. 10
• 3] Rs. 11
• 4] Rs. 12

The average of 9 observations was found to be 35. Later on, it was detected that an observation 81 was misread as 18. The correct average of the observation is -

• 1] 28
• 2] 42
• 3] 32
• 4] 45

Four years ago, the average age of A and B was 18 years. At present the average age of A, B, and C is 24 years. What would be the age of C after 8 years?

• 1] 25 years
• 2] 28 years
• 3] 32 years
• 4] 36 years

The average weight of 47 balls is 4 g. if the weight of the bag (in which the balls are kept) be included; the calculated average weight per ball increases by 0.3 g. What is the weight of the bag?

• 1] 14.8 g
• 2] 14.4 g
• 3] 15 g
• 4] 18.6 g
• 5] None of these

Find the average of 205, 302, 108, 403, and 202-

• 1] 450
• 2] 1125
• 3] 244
• 4] 1220

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