Quiz Discussion

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

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

• 1]

  40

• 2]

  39

• 3]

  52

• 4]

  55

The average monthly income of P and Q is Rs. 6000; that of Q and R is Rs. 5250; and that P and R is Rs. 5500. What is P’s monthly income?

• 1] Rs. 3500
• 2] Rs. 4500
• 3] Rs. 6250
• 4] Rs. 4800

Mean of 10 numbers is 30. Later on it was observed that numbers 15, 23 are wrongly taken as 51, 32. The correct mean is :

• 1] 25.5
• 2] 32
• 3] 30
• 4] 34.5

Find the average of the first 40 natural numbers.

• 1]

  21

• 2]

  20.5

• 3]

  21.5

• 4]

  None Of These

Five years ago, the average age of P and Q was 25. The average age of P, Q and R today is 25. Age of R after 5 years will be :

• 1] 15 years
• 2] 20 years
• 3] 40 years
• 4] 35 years

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

One-fourth of certain journey is covered at the rate of 25 km/h, one-third at the rate of 30 km/h and the rest at 50 km/h. Find the average speed for the whole journey.

• 1]

  600/53 km/h

• 2]

  1200/53 km/h

• 3]

  1800/53 km/h

• 4]

  1600/53 km/h

• 5]

  None of these

The average age of the mother and her six children is 12 years which is reduced by 5 years if the age of the mother is excluded. How old is the mother ?

• 1] 40 years
• 2] 42 years
• 3] 48 years
• 4] 50 years

Five years ago the average age of A, B, C, D was 45 years. By including X the present average of all the five is 49 years. Them the present age of X is-

• 1] 40 years
• 2] 45 years
• 3] 48 years
• 4] 64 years