Question:

The variance of two observations 10 and 17 is

A.

12.25

B.

12

C.

1.225

D.

13

Answer» a. 12.25

Question:

The frequencies of three class intervals 54 – 58, 59 – 63, 64 – 68 of a distribution arerespectively 4, 8 and 12. The frequency density of the 2nd class is

A.

1

B.

1.2

C.

1.6

D.

2

Answer» d. 2

Question:

The G.M of 3 and 24 with weight 2 and 1 respectively is

A.

8

B.

4

C.

6

D.

9

Answer» c. 6

Question:

If the events A and B are mutually exclusive then

A.

P (A + B) = P (A) + P (B)

B.

P (A + B) = P (A) – P (B)

C.

P (A + B) = P (A) P (B)

D.

P (A + B) = 0 18

Answer» a. P (A + B) = P (A) + P (B)

Question:

For a symmetric distribution, skewness is

A.

0

B.

1

C.

-1

D.

0.5

Answer» a. 0