BUSINESS STATISTICS
ASSIGNMENT A
1. Define time series. Describe moving average method.
2 . What do you mean by Primary & Secondary data. What are the methods to collect them ?
3 . What is a Hypothesis ? Write the procedure for testing a Hypothesis.
4 . What is the diffrence between census & sample survey. Write steps in sampling design.
5 . A biased coin is tossed 6 times. The probability of heads on any toss is 0.3. Let X denote the number of heads that come up. Calculate: (i) P(X = 3) (ii) P(1 < X ≤ 5)
6 . The number of calls coming per minute into a hotels reservation center is Poisson random variable with mean 3. Find the probability that no calls come in a given 1 minute period.
ASSIGNMENT B
CASE STUDY
Case Detail :
The length of life of an instrument produced by a machine has a normal ditribution with a mean of 12 months and standard deviation of 2 months. Find the probability that an instrument produced by this machine will last
Q1.
between 7 and 12 months.
Q2.
less than 7 months.
Q3.
more than 5 months but less than 10 months
ASSIGNMENT C
1.The mean age of combined group of men and women is 25 years. If the mean age of group of men is 26 and that of group of women is 21, then percentage of men and women in the group respectively is:
Options
60,40
80,20
30,70
50,50
2.What is the weighted mean of first 10 natural numbers whose weights are equal to the corresponding number?
Options
7
5,5
5
4,5
3.Sum of mode and median of the data
Options
26
31
28
41
4.The mean of 9 observations is 16. One more observation is included and the new mean becomes 17. The 10th observation is
Options
18
30
7
26
5 Given third quartile is 80 & first quartile is 20 then semi-inter quartile range is
Options
100
60
30
40
6.Given third quartile is 100 & first quartile is 25 then coefficient of Quartile Deviation
Options
6
75
0.6
125
7.Given mean is 45 & standard deviation is 15 then coefficient of variation is
Options
30
33.33
34
33
8.Given, covariance of (x ,y )=10 variance of x =49,variance of y =100,correlation between x and y is
Options
5/8
7/8
1/3
1/7
9.Coefficient of non-determination is
Options
1-r2
r2 -1
r2
1+ r2
10.In binomial probability distribution, the dependents of standard deviations must includes
Options
probability of q
probability of p
Trials
all options
11,The formula to calculate standardized normal random variable is
Options
x + μ ⁄ σ
x - μ ⁄ σ
x - σ ⁄ μ
x + σ ⁄ μ
12.In binomial distribution, the formula of calculating standard deviation is
Options
square root of p
square root of pq
square root of npq
square root of np
13.The tail or head, the one or zero and the girl and boy are examples of
Options
non functional events
complementary events
non complementary events
functional events
14.The method of calculating skewness which is based on the positions of quartiles and median in a distribution is called
Options
Gary's coefficient of skewness
Sharma's coefficient of skewness
Bowley's coefficient of skewness
Jack Karl's coefficient of skewness
15.The median of a moderately skewed distribution is 8, third quartile is 12, first quartile is 8 and inter-quartile range is 4 then relative coefficient of skewness is
Options
±8
±1
±9
±11
16.The kurtosis defines the peakness of the curve in the region which is
Options
around the mode
around the mean
around the median
around the variance
17.In measures of skewness, the absolute skewness is equal to
Options
mean+mode
mean-mode
mean+median
mean-median
18.If for a distribution the difference of first quartile and median is less than difference of median and third quartile then the distribution is classified as
Options
negatively skewed
not skewed at all
absolute open ended
positively skewed
19.The three times of difference between mean and median is divided by standard deviation to calculate coefficient of skewness by method of
Options
Professor Keller
Professor Kelly
Karl Pearson
Professor Bowley
20.If the standard deviation of the population is 35 and the sample size is 9 then the standard deviation of sampling distribution is
Options
12.67
11.67
13.67
14.67
________________________________________
21.In statistical analysis, the sample size is considered large if
Options
n > or = 30
n < or = 30
n > or = 40
n < or = 50
22.If the mean of population is 25 then the mean of sampling distribution is
Options
50
25
30
20
23.The standard deviation of a sampling distribution is also classified as
Options
standard error
statistic error
sampling error
probability error
24.In sampling distribution, the formula of calculating standard deviation of sample proportion is as
Options
square root of pqn ⁄ p
square root of pn ⁄ q
square root of nq ⁄ p
square root of pq ⁄ n
25.The numerical methods and graphical methods are specialized procedures used in
Options
social statistics
education statistics
descriptive statistics
business statistics
26.The focus groups, individual respondents and panels of respondents are classified as
Options
pointed data sources
itemized data sources
secondary data sources
primary data sources
27.The collection of all the elements such as group of variables for research is classified as
Options
statistical process
population
data
marginal error
28.In linear programming, the constraints can be represented by
Options
equalities
inequalities
ratios
both 1 and 2
29.The feasible region's optimal solution for a linear objective function always includes
Options
downward point
upward point
corner point
front point
30.The objective of linear programming for an objective function is to
Options
subset or proper set modeling
maximize or minimize
row or column modeling
adjacent modeling
31.In linear programming, the objective function and objective constraints are
Options
quadratic
solved
linear
adjacent
32.In maximization problem, the optimal solution occurring at the corner point yields the
Options
mean values of z
mid values of z
lowest value of z
highest value of z
33.If the arithmetic mean is multiplied to coefficient of variation then the resulting value is classified as
Options
coefficient of deviation
coefficient of mean
standard deviation
variance
34.The formula of coefficient of range is
Options
L+L ⁄ H+H
H+l ⁄ H-L
H-L ⁄ H+L
H+H ⁄ L+L
35.Considering the standard deviation, the mean absolute deviation is equal to
Options
5⁄4 σ
7⁄8 σ
5⁄8 σ
4⁄5 σ
36.The sum of highest and lowest value is 80 and the coefficient of range is 0.625 then the difference between highest and lowest value is
Options
50
70
80
48
37.The value of third quartile is 61 and inter quartile range of the set of observation is 48 then value of first quartile is
Options
24
34
64
13
38.Which is the best method to find trend
Options
free hand
least square
moving average
semi average
39.Components of time series are
Options
T,S,C.I
T,S.P.I
T,C,S,P
T,I,C.P
40.Regression lines intersect at
Options
mean values
median
mode
correlation