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

Find the range of the following: 500, 630, 720, 520, 480, 870, 960,450

The value of \ $\frac{6.35 \times 6.35 \times 6.35 + 3.65 \times 3.65 \times 3.65}{63.5 \times 63.5 + 36.5 \times 36.5 - 63.5 \times 36.5}$ is equal to

If x + y + z = 19, xyz = 216 and xy + yz + zx = 114, then the value of $\sqrt{x^3+y^3+z^3+xyz}$ is.

Which of the following are measures of dispersion?

Range
Mean
Variance
Standard deviation

The value of $\frac{5.35\times{5.35}\times{5.35}+3.65\times{3.65}\times{3.65}}{53.5\times{53.5}+36.5\times{36.5}-53.5\times{36.5}}$ is:

Which of the following are the properties of dispersion?

It should be rigidly defined
It should be based on all the observations
It should be simple to understand and easy to calculate
It should be capable of further algebraic treatments

The degree of scatter or variation of the observations in a data about a central value is called

If $\sqrt{11-3\sqrt{8}}=a+b\sqrt{2}$ , then what is the value of (2a+3b)?

When 5 children from class A join class B, the number of children in both classes is the same. If 25 children from B, join A, then the number of children in A becomes double the number of children in B. The ratio of the number of children in A to those in B is:

If (10a³ + 4b³) : (11a³ - 15b³) = 7 : 5, then (3a + 5b) : (9a - 2b) =?

If 27(x + y)³ - 8(x - y)³ = (x + 5y)(Ax² + By² + Cxy), then what is the value of (A + B - C)?

Two positive numbers differ by 1280. When the greater number is divided by the smaller number, the quotient is 7 and the remainder is 50. The greater number is:

If a + b + c = 6, a³ + b³ + c³ - 3 abc = 342, and a² + b² + c² = 50, then what is the value of ab + bc + ca?

If a and b are two positive real numbers such that a + b = 20 and ab = 4, then the value of a³ + b³ is:

If a = 355, b = 356, c = 357, then find the value of a³ + b³+ c³ - 3abc.

If a + b = 10 and $\frac{3}{7}$ of ab = 9, then the value of a³ + b³ is:

If xy = 16 and x² + y² = 32, then the value of (x + y) is:

Find the factors of the expression 3x² – 5x – 8.

If $x^4+\frac{1}{x^4}=\frac{257}{16}$ then find $\frac{8}{13}(x^3+\frac{1}{x^3})$ , where x>0.

If a + b = 8 and a + a² b + b + ab² = 128 then the positive value of a³+ b³ is:

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