Q1.

If x and y are related by x - y - 35 = 0 and median of x is 44, then find the median of y.

  • 9

  • 10

  • 11

  • 12

Solution:

NA

Q2.

If the mean and standard deviation of x are c and k respectively, then the S.D. of (x - c)/k is 

  • 2

  • 1

  • k

  • c

Solution:

NA

Q3.

A sample of 35 observations has the mean 80 and S.D. as 4. A second sample of 65 observations from the same population has mean 70 and S.D. 3. The S.D. of the combined sample is : 

  • 5.85

  • 5.67

  • 10

  • None of these 

Solution:

NA

Q4.

The Mean and S.D. for group of 100 observations are 65 and 7.03 respectively . If 60 of these observations have mean and S.D. as 70 and 3 respectively, what is the S.D. for the group comprising 40 observations ? 

  • 2.03

  • 4.03

  • 8.03

  • 9.33

Solution:

NA 

Q5.

Mean and S.D. of a given set of observations is 1,500 and 400 respectively . If there is an increment of 100 in the first year and each observation is hiked by 20% in 2nd years, then find new mean and S.D. 

  • 1920, 480

  • 1920, 580

  • 1600, 480

  • 1600, 400

Solution:

NA

Q6.

If 5 is subtracted from each observation of some certain item then its co-efficient of variation is 10% and if 5 is added to each item then its coefficient of variation is 6%. Find original coefficient of variation. 

  • 8%

  • 7.5%

  • 4%

  • None of these 

Solution:

NA

Q7.

The sum of squares of deviation from mean of 10 observations is 250. Mean of the data is 10. Find the co-efficient of variation. 

  • 10% 

  • 25%

  • 50%

  • 0%

Solution:

NA

Q8.

If the difference between Mean and Mode is 63, then the difference between Mean and Median will be __________________ . 

  • 63

  • 31.5

  • 21

  • None of these 

Solution:

NA

Q9.

If all observations in a distribution are increased by 6, then the variance of the series will be _____________ . 

  • Increased

  • Decreased

  • Unchanged

  • None of these 

Solution:

NA

Q10.

The median of following numbers, which are given is ascending order is 25. Find the value of X. 

11   13   15   19   (x + 2)   (x + 4)   30   35   39   46  

  • 22

  • 20

  • 15

  • 14

Solution:

NA

Q11.

The average age of a group of 10 students was 20 years . The average age increased by two years when two new students joined the group. What is the average age of two new students who joined the group ? 

  • 22 years 

  • 30 years 

  • 44 years 

  • 32 years 

Solution:

NA

Q12.

If the mode of a data is 18 and mean is 24, then median is -

  • 18

  • 24

  • 22

  • 21

Solution:

NA

Q13.

The point of intersection of the "less than" and "more than" ogives correspond to 

  • Mean

  • Mode 

  • Median

  • 10th Percentile 

Solution:

NA

Q14.

The average age of 15 students of a class is 15 years . Out of them , the average age of 5 students is 14 years and that of the other 9 students is 16 years. The age of the 15th student is :

  • 11 years

  • 14 years

  • 15 years

  • None of these 

Solution:

NA

Q15.

The price of averages whose value can be determined graphically ? 

  • Mode, Median

  • Mean, Mode 

  • Mean, Median

  • None of these 

Solution:

NA

Q16.

The third decile for thr numbers 15, 10, 20, 25, 18, 11, 9, 12, is:

  • 13

  • 10.70

  • 11

  • 11.50

Solution:

NA

Q17.

If the first quartile is 142 and semi-inter quartile range is 18, then the value of median is : 

  • 151

  • 178

  • 155

  • 160

Solution:

NA

Q18.

If the arithmetic mean of two numbers is 10 and the geometric mean od these numbers is 8, then the harmonic mean is : 

  • 9

  • 8.9

  • 6.4

  • None of these 

Solution:

NA

Q19.

The standard deviation of a variable x is known to be 10. The standard deviation of 50 + 5x is 

  • 50

  • 100

  • 10

  • 500

Solution:

NA

Q20.

If all the observations are increased by 5, then  

  • S.D.  would be increased by 5 

  • Mean deviation would be increased by 5 

  • Quartile deviation would be increased by 5 

  • All the three would not be increased by 5

Solution:

NA

Q21.

The SD of first n natural number is _____________ . 

  • \( \sqrt{n^2-1\over 12}\)

  • \( \sqrt{n(n + 1)\over 12}\)

  • \( \sqrt{n(n - 1)\over 12}\)

  • None of these 

Solution:

NA

Q22.

A population P has 30 observations 21, 22, 23,--------60, and another population Q has 30 observations 51, 52, 53,--------80.If S.DA and S.DB represents the standard deviation of the two populations respectively. Then find the value of (S.DA/ S.DB)2 

  • 1

  • 2

  • 3

  • 4

Solution:

NA

Q23.

If two variables x and y are related by 3x + 5y - 10 = 0, and median and mean deviation about median of x are 2 and 1 respectively. Find the coefficient of mean deviaton of y about median is

  • 38

  • 75

  • 80

  • 23

Solution:

NA

Q24.

In a set of 100 observations, taking assumed mean as 4, the sum of the deviations is -11 unit, and the sum of the squares of these deviations is 257 square unit. The coefficient of varation is-------%

  • 45

  • 44.12

  • 41.12

  • 55

Solution:

NA