Which of the following is not a measure of dispersion?
Arithmetic mean
The range of the data 8, 8, 8, 8, 8. . . 8 is
0
The sum of all deviations of the data from its mean is
zero
The mean of 100 observations is 40 and their standard deviation is 3. The sum of squares of all deviations is
160900
Variance of first 20 natural numbers is
33.25
The standard deviation of a data is 3. If each value is multiplied by 5 then the new variance is
225
If the standard deviation of x, y, z is p then the standard deviation of 3x+5 , 3y+5, 3z+5 is
3p
If the mean and coefficient of variation of a data are 4 and 87.5% then the standard deviation is
3.5
Which of the following is incorrect?
P(A)> 1
The probability a red marble selected at random from a jar containing p red, q blue and r green marbles is
p/p+q+r)
A page is selected at random from a book. The probability that the digit at units place of the page number chosen is less than 7 is
7/10
The probability of getting a job for a person is x/3 . If the probability of not getting the job is 2/3 then the value of x is
1
Kamalam went to play a lucky draw contest. 135 tickets of the lucky draw were sold. If the probability of Kamalam winning is 1/9 , then the umber of tickets bought by Kamalam is
15
If a letter is chosen at random from the English alphabets {a,b,...,z}, then the probability that the letter chosen precedes x
23/26
A purse contains 10 notes of Rs..2000, 15 notes of Rs..500, and 25 notes of Rs..200. One note
is drawn at random. What is the probability that the note is either a Rs.500 note or
Rs. 200 note?
4/5