Statistics MCQS for NTS Set 2

Var (2x + 3) is:

4 Var (x)

4 Var (x) +9

4 Var (x) +3

5 var (x)

if m = 130, X? = 150,s = 5,n =10, what test statistic is appropriate?

F

t

X²

Z

A decimal number system has base

16

8

2

10

Second moment about mean is

Standard Deviation

Zero

Variance

One

The value of correlation co-efficient lies between

-1 to 0

-1 to +1

-0.5 to +0.5

0 to +1

The sum of the squares of deviation is least form:

Mode

Harmonic mean

Median

Mean

If var (x) =5, var(y) =10, then var (2x + y) is:

25

15

30

10

By decreasing ×? the length of confidence interval for m

None of these

Increases

Decreases

No effect

Is a normal distribution ? = 10 and ?² = 25 the mode is

5

25

10

100

In unimodal distribution If mode is less than mean then distribution is

Symmetrical

Positively skewed

Negatively skewed

Normal