BCSL-044 Solved Assignment 2020-21 | Statistical Techniques Lab

Description

Course Code :	BCSL-44
Course Title :	Statistical Techniques Lab
Assignment Number :	BCA(4)/044/Assignment/2020-21
Maximum Marks :	50
Weightage :	25%
Last Date of Submission :	15th October, 2020 (for July 2020 session) 15th April, 2021 (for January 2021 session)
Solution Type :	Softcopy (PDF File)

There are six questions in this assignment, which carries 40 marks. Rest 10 marks are for viva-voce. Answer all the questions. Please go through the guidelines regarding assignments given in the Programme Guide for the format of presentation.
All the following questions must be performed using a statistical package. You may use any statistical package for this purpose.

Q1.Weight of students of a class having 40 student was recorded. This data is given in the following table. Perform the tasks given in (i) to (iv) on the data given below using a spreadsheet package:

42	54	60	55	49	46	55	38	65	40
61	46	47	42	51	53	59	57	46	60
52	54	50	60	58	44	49	39	48	56
47	53	52	57	55	44	51	47	61	43

(i) Find the minimum and maximum weight using the spreadsheet formula
(ii) Create 6 classes with suitable class intervals and create the frequency distribution. You must use Array formula.
(iii) Find the percentage of the students whose weight is less than the mean weight
(iv) Draw the histogram for the data above. Also try to relate it to normal distribution curve.

Q2. Perform the following tasks using a spreadsheet (you may use spreadsheet function for computing the value of t):

(i) Find the value of t for the given value of degree of freedom and significance level (alpha):

Degree of freedom	Significance
15	0.05
8	0.10

(ii) A company manufactures milk packets of 1 litre. A sample of 20 such packet were taken out of a lot consisting of 1000 packets. The mean sample volume was found to be 1.0025 litre having a standard deviation of 0.04 litre. Assuming random sampling and a confidence level of 95%, will you accept the milk packets. Justify your answer. Make suitable assumption, if any.

Q3. A Company produces brake liners of thickness 6.4 mm. The company has four different machines to produce break liners. Each day five samples of each machine are taken and thickness of the break liner is determined. The following tables lists these details:

The thickness of break lines (in mm)

Sample	Machine Identifier
	A	B	C	D
1	6.4001	6.3999	6.3903	6.4000
2	6.4011	6.3965	6.3803	6.4009
3	6.4035	6.3923	6.3703	6.3990
4	6.4101	6.3910	6.3995	6.3910
5	6.4071	6.3900	6.3918	6.4030

Perform an ANOVA using any software to test (at 5% level) whether all the four machines are producing the break lines with correct thickness. Justify your findings. Make suitable assumptions, if any.

Q4. Exchange rate of currency X against currency Y for the first 15 days of July, 2020 are shown in the following table. Use spreadsheet software to find the moving averages for the length of 3 and 5. Also draw suitable graphs of these moving averages.

Day	Sales in Thousand Rupees
1	65
2	61
3	62
4	63
5	64
6	65
7	66
8	62
9	59
10	61
11	64
12	60
13	60
14	64
15	66

Q5.A company packs flour in packets of 5 Kilograms. The quality of process of producing the flour packet is controlled statistically. To do so, sample of five packets is taken at four different times of the day. Calculate the control limits for mean and range, and plot the control charts using any statistical software. Make suitable assumptions, if any.

The data is given in the following table:

Sample id of the day	The weight of the flour in 5 samples (in Kgs)
1	5.10	5.25	4.95	5.30	5.08
2	5.19	5.02	5.10	5.16	4.91
3	5.04	5.11	4.92	4.89	4.93
4	5.05	5.14	4.98	4.92	5.13

(Please take the suitable values of d2 , d3, d4 , A2 and other variables.)

Q6.The following table shows the sale of mobiles by a company in different months. Fit a trend line using any statistical software to this sales data. Make suitable assumptions.

Month	Jan	Feb	Mar	Apr	May	Jun	July
Sales (in No of Units)	2000	1900	1950	1800	1600	1600	1800

 

All questions are solved in this assignment solution.