The average of a set of 30 numbers is 25. If three numbers 13, 15 and 20 are discarded, then the average of the remaining numbers is

The measure of dispersion which uses only two observations is called:

Any measure indicating the centre of a set of data, arranged in an increasing or decreasing order of magnitude, is called a measure of:

The sum of the squares of the deviations of the values of a variable is least when the deviations are measured from:

The sum of deviations taken from mean is:

The frequency distribution of diameter (D) of 101 steel balls is given in the following list-

D(mm)	43	44	45	46	47	48
No.	13	15	22	21	16	14

find the mean of the diameter in mm

If the value of mean and mode of a grouped data are 50.25 and 22.5 respectively, then by using the empirical relation, find the median for the grouped data.

If the mean of the following frequency distribution is 8. Find the value of p.

x	2	4	6	p+6	10
f	3	2	3	3	2

Study the following graph and answer the question given below. The below Histogram shows the data of the annual rainfall (in cm).

Find the difference in the number of times the rainfall above 130 cm and the number of times the annual rainfall below 130 cm.

Study the following graph and answer the question given below. The below Histogram shows the data of the annual rainfall (in cm).

The number of times annual rainfall below 120 cm is what percent of the number of times the annual rainfall above 130 cm?

Study the following graph and answer the question given below.

What percentage (approx.) of the employees working in the range of Rs. 30,000 - Rs. 40,000?

If the median and the mode of a set of data are 12 and 15, respectively, then find the value of thrice the mean of the same data set.

If A, B and C are denoting Mean, Median and Mode of a data and A ∶ B = 9 ∶ 8 then the ratio of B ∶ C is:

Find the mean deviation about the mean of the distribution:

Size	20	21	22	23	24
Frequency	6	4	5	1	4

The standard deviation of the data 6, 5, 9, 13, 12, 8, 10 is

The variance of 6, 8, 10, 12, 14, 16 is:

A histogram is to be drawn for the following frequency distribution

Class Interval	5-10	10-15	15-25	25-45	45-75
Frequency	6	12	10	8	15

The adjusted frequency for class interval 15 - 25 will be :

Find the range and the coefficient of the range of the following data:

Marks 20 - 30, 30 - 40, 40 - 50, 50 - 60, 60 - 70, 70 - 80, 80 - 90

No. of Students = 10, 12, 15, 20, 25, 13, 38

What is the mean of data given in table?

Value (X)	Frequency (Y)
6	25
3	30
5	40
2	35
4	12
6	26

Calculate the mean of the following table:

Interval	f_i
0-10	6
10-20	5
20-30	7
30-40	8
40-50	3

The mean of the observations 29, x + 1, 33, 44, x + 3, x + 6 and 46 is 39. Then, the median of the observations is :

The median of the observations 11, 12, 14, 18, x + 2, 22, 22, 25 and 61, arranged in ascending order, is 21. Then, value of 3x + 7 is:

Following table shows marks obtained by 40 students. What is the mode of this data ?

Marks obtained	42	36	30	45	50
No. of students	7	10	13	8	2

The mean of 10 observations was calculated as 40. It was detected on rechecking that the value of one observation 45 was wrongly copied as 15. Find the correct mean.

What is the sum of mean, mode and median of the following data?

14, 9, 12, 11, 15, 28, 23, 17, 28, 53 ?

If (a + b + c) = 17, and (a²+ b² + c²) = 101, find the value of (a - b)² + (b - c)² + (c - a)².

If $(4y-\frac{4}{y})=11$ , find the value of $(y^2+\frac{1}{y^2})$ .

If $x-\frac{1}{x} = 3$ , then the value of $x^3-\frac{1}{x^3}$ is

f (a + b + c) = 12, and (a²+ b² + c²) = 50, find the value of (a³ + b³ + c³ - 3abc)

If, $(x+\frac{1}{x})=4$ , then the value of $x^4+\frac{1}{x^4}$ is:

If x + y = 4, then the value of (x³ + y³ + 12xy) is

If $x^4+\frac{1}{x^4}=34$ , then the value of $(x-\frac{1}{x})^2$ will be

If a is positive and $a^2+\frac{1}{a^2}=7$ , thenfind $a^3+\frac{1}{a^3}$ .

If a = 299, b = 298, c = 297 then the value of 2a³ + 2b³ + 2c³ – 6abc is:

If a = 0.125 then what is value of $\sqrt{4a^2-4a+1}+3a$ ?

A sales executive marketed 84 items in a week on an average with a standard deviation of 18. Find the coefficient of variation:

Find the variance of first 30 natural numbers

What is the square of standard deviation is called

Calculate the sd of the following data 3, 4, 9, 11, 13, 6, 8, 10.

Which of the following is the minimum value of standard deviation

Which of the following not false

the square root of the mean of squares of deviations of observations from their mean is standard deviation
The variability of a data will decrease if sd increases
The stability or the consistency of a data increases as sd decreases
The data with less sd is better than a data with high sd provided that the two data were expressed with the same unit.

the square root of the mean of squares of deviations of observations from their mean is called

Find the mean deviation about the median for the following data 3, 9, 5, 3, 12, 10, 18, 4, 7, 19, 21

Determine the mean deviation for the data value 5,3,7,8,4,9

Find the range of numbers 8,6,5,2,1,10,16,19,22,26,25

Calculate quartile deviation for the following data: 30,18, 23, 15, 11, 29, 37,42, 10, 21

Find the quartiles and quartile deviation of the following data: 17, 2, 7, 27, 15, 5, 14, 8, 10, 24, 48, 10, 8, 7, 18, 28

Find the range of 21,12,22,32,2,35,64,67,98,86,76

Find the range 61,22,34,17,81,99,42,94

Calculate the quartile deviation of the following data: 500, 630, 750, 300, 129, 357, 100, 110, 117

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