# If the mean of 5 observations x, x + 2, x + 4, x + 6 and x + 8 is 11, then the mean of the last three observations is:

1.  11

2.  13

3.  15

4.  17

4

13

Explanation :
No Explanation available for this question

# 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

4

3M2

Explanation :
No Explanation available for this question

# A student was asked to find the arithmetic mean of the numbers 3, 11, 7, 9, 15, 13, 8, 19, 17, 21, 14 and x. He found the mean to be 12. What should be the number in place of x

1.  3

2.  7

3.  17

4.  31

4

7

Explanation :
No Explanation available for this question

# The average of the two-digit numbers, which remain the same when the digits interchange their positions, is:

1.  33

2.  44

3.  55

4.  66

4

55

Explanation :
No Explanation available for this question

# The average of first 50 numbers is:

1.  12.25

2.  21.25

3.  25

4.  25.5

4

25.5

Explanation :
No Explanation available for this question

# The mean o 12, 22, 32, 42, 52, 62, 72 is:

1.  10

2.  20

3.  30

4.  40

4

20

Explanation :
No Explanation available for this question

# The average of all odd numbers upto 100 is:

1.  49

2.  49.5

3.  50

4.  51

4

50

Explanation :
No Explanation available for this question

# The average of a non-zero number and its square is 5 times the number. The number is:

1.  9

2.  17

3.  29

4.  295

4

9

Explanation :
No Explanation available for this question

# The average of 7 consecutive numbers is 20. The largest of these numbers is:

1.  20

2.  22

3.  23

4.  24

4

23

Explanation :
No Explanation available for this question

# The average of five consecutive odd numbers is 61. What is the difference between the highest and lowest numbers

1.  2

2.  5

3.  Cannot be determined

4.  None of these

4