Complete Study Pack for Engineering Entrances Objective Mathematics Vol 1>Chapter 20 - Statistics>Target Exercises>Q 12

MEDIUM

JEE Advanced

IMPORTANT

Earn 100

The algebraic sum of the deviations of $20$ observations measured from $30$ is $2$ . The mean of observations is

50% studentsanswered this correctly

Important Questions on Statistics

MEDIUM

JEE Advanced

IMPORTANT

Complete Study Pack for Engineering Entrances Objective Mathematics Vol 1>Chapter 20 - Statistics>Target Exercises>Q 13

A class of

30

boys and

15

girls is given a test in mathematics. The average marks obtained by boys is

15

and by girls is

6

. The average of whole class is

MEDIUM

JEE Advanced

IMPORTANT

Complete Study Pack for Engineering Entrances Objective Mathematics Vol 1>Chapter 20 - Statistics>Target Exercises>Q 14

If the arithmetic mean of

9

observations is

100

and that of

6

is

80

. Then, the combined mean of all the

15

observations will be

MEDIUM

JEE Advanced

IMPORTANT

Complete Study Pack for Engineering Entrances Objective Mathematics Vol 1>Chapter 20 - Statistics>Target Exercises>Q 15

Combined mean of two series

x_{1}

and

x_{2}

, when

Σ x_{1} = 210, Σ x_{2} = 150, n_{1} = 50, n_{2} = 100

is

MEDIUM

JEE Advanced

IMPORTANT

Complete Study Pack for Engineering Entrances Objective Mathematics Vol 1>Chapter 20 - Statistics>Target Exercises>Q 16

The mean income of a group of workers is

X

and that of another group is

Y

. If the number of workers in the second group is

10

times the number of workers in the first group, then mean income of combined group is

MEDIUM

JEE Advanced

IMPORTANT

Complete Study Pack for Engineering Entrances Objective Mathematics Vol 1>Chapter 20 - Statistics>Target Exercises>Q 17

The mean age of a combined group of men and women is

25

years. If the mean age of men is

26

years and that of women is

21

years, then the percentage of men and women in the group are

MEDIUM

JEE Advanced

IMPORTANT

Complete Study Pack for Engineering Entrances Objective Mathematics Vol 1>Chapter 20 - Statistics>Target Exercises>Q 18

A set of

7

observations has mean

10

and another set of

3

observations has mean

5

. The mean of combined set is

MEDIUM

JEE Advanced

IMPORTANT

Complete Study Pack for Engineering Entrances Objective Mathematics Vol 1>Chapter 20 - Statistics>Target Exercises>Q 19

If

{\bar{x}}_{1}

and

{\bar{x}}_{2}

are means of two distribution, such that

{\bar{x}}_{1} < {\bar{x}}_{2}

and

\bar{x}

is the mean of the joint distribution, then

EASY

JEE Advanced

IMPORTANT

Complete Study Pack for Engineering Entrances Objective Mathematics Vol 1>Chapter 20 - Statistics>Target Exercises>Q 20

If

G_{1}

and

G_{2}

are geometric means of two series and

G

is

G . M

of the ratio of corresponding series, then

G

is