Class 9 EM Statistics

Let m be the mid point and b be the upper limit of a class in a continuous frequency distribution. The lower limit of the class is

• 2m - b

• 2m + b

• m - b

• m - 2b

The mean of a set of seven numbers is 81. If one of the numbers is discarded, the mean of the remaining numbers is 78. The value of discarded number is

• 101

• 100

• 99

• 98

A particular observation which occurs maximum number of times in a given data is called its

• Frequency

• Range

• Mode

• Median

For which set of numbers do the mean, median and mode all have the same values?

• 2, 2, 2, 4

• 1, 3, 3, 3, 5

• 1, 1, 2, 5, 6

• 1, 1, 2, 1, 5

The algebraic sum of the deviations of a set of n values from their mean is

• 0

• n - 1

• n

• n + 1

The mean of a, b, c, d and e is 28. If the mean of a, c and e is 24, then mean of b and d is

• 24

• 36

• 26

• 34

If the mean of five observations x, x + 2, x + 4, x + 6, x + 8 is 11, then the mean of first three observations is

• 9

• 11

• 13

• 15

The mean of 5, 9, x, 17 and 21 is 13, then find the value of x

• 9

• 13

• 17

• 21

The mean of the square of first 11 natural numbers is

• 26

• 46

• 48

• 52

The mean of a set of numbers is  $\overline{X}$ . If each number is multiplied by z, the mean is 

•  $\overline{X}+z$  

•  $\overline{X}-z$  

•  $z\ \overline{X}$  

•  $\overline{X}$