Arts (English Medium) Class 11 - CBSE Question Bank Solutions

Mean and standard deviation of 100 items are 50 and 4, respectively. Find the sum of all the item and the sum of the squares of the items.

Find the mean and variance of the frequency distribution given below:

Calculate the mean deviation about the mean for the following frequency distribution:

Calculate the mean deviation from the median of the following data:

Determine mean and standard deviation of first n terms of an A.P. whose first term is a and common difference is d.

While calculating the mean and variance of 10 readings, a student wrongly used the reading 52 for the correct reading 25. He obtained the mean and variance as 45 and 16 respectively. Find the correct mean and the variance.

The mean deviation of the data 3, 10, 10, 4, 7, 10, 5 from the mean is ______.

Mean deviation for n observations x₁, x₂, ..., x_n from their mean `barx` is given by ______.

When tested, the lives (in hours) of 5 bulbs were noted as follows: 1357, 1090, 1666, 1494, 1623 
The mean deviations (in hours) from their mean is ______.

The mean of 100 observations is 50 and their standard deviation is 5. The sum of all squares of all the observations is ______.

If `barx` is the mean of n values of x, then `sum_(i = 1)^n (x_i - barx)` is always equal to ______. If a has any value other than `barx`, then `sum_(i = 1)^n (x_i - barx)^2` is ______ than `sum(x_i - a)^2`

The sum of squares of the deviations of the values of the variable is ______ when taken about their arithmetic mean.

In the following, state whether A = B or not:

A = {a, b, c, d}; B = {d, c, b, a}

In the following, state whether A = B or not:

A = {4, 8, 12, 16}; B = {8, 4, 16, 18}

In the following, state whether A = B or not:

A = {2, 4, 6, 8, 10}; B = {x : x is positive even integer and x ≤ 10}

In the following, state whether A = B or not:

A = {x : x is a multiple of 10}; B = {10, 15, 20, 25, 30, ...}

Are the following pair of sets equal? Give reasons.

A = {2, 3}, B = {x : x is solution of x² + 5x + 6 = 0}

Are the following pair of sets equal? Give reasons.

A = {x : x is a letter in the word FOLLOW};

B = {y : y is a letter in the word WOLF}

From the sets given below, select equal sets:

A = {2, 4, 8, 12},
B = {1, 2, 3, 4},
C = {4, 8, 12, 14},
D = {3, 1, 4, 2},
E = {-1, 1},
F = {0, a},
G = {1, -1},
H = {0, 1}

Assume that P (A) = P (B). Show that A = B.