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## #2 Exercises » Statistics » 2020-06-08 07:46:55

Zeeshan 01
Replies: 4

Q.1 Given are five observations for two variables, x and y.
Xi 3 12 6 20 14
yi 55 40 55 10 15
a. Develop a scatter diagram for these data.
b. What does the scatter diagram developed in part (a) indicate about the relationship between the two variables?
c. Try to approximate the relationship between x and y by drawing a straight line through the data.
d. Develop the estimated regression equation by computing the values of b0 and b1.
e. Use the estimated regression equation to predict the value of y when x = 10.

Q.2 The following data give the percentage of women working in five companies in the retail and trade industry. The percentage of management jobs held by women in each company is also shown.
%Working 67 45 73 54 61
% Management 49 21 65 47 33
a. Develop a scatter diagram for these data with the percentage of women working in the company as the independent variable.
b. What does the scatter diagram developed in part (a) indicate about the relationship between the two variables?
c. Try to approximate the relationship between the percentage of women working in the company and the percentage of management jobs held by women in that company.
d. Develop the estimated regression equation by computing the values of b0 and b1.
e. Predict the percentage of management jobs held by women in a company that has 60% women employees.

## #3 Coder's Corner » Assembly Language Programs [Fast] » 2020-03-04 19:58:14

Zeeshan 01
Replies: 0

In Assembly:

Question 1 :Str1 DB ' & 12 ABC ; YQm '

Output : Only Print Capital Letters ie ABYQ

Question 2 : str2 DB 'AKMNYQ'

Output : Largest AscII print;    that is min = A , max = y

Question3:  Srt3 DB  ' ihmabdra

Output: i space hma space bdra space

## #4 Help Me ! » Integration » 2020-02-15 06:21:36

Zeeshan 01
Replies: 1

Proof that  integration of y with respect to x is .

## #5 Exercises » Calculus MCQS IMPORTANT [Part 2] » 2019-12-29 07:24:45

Zeeshan 01
Replies: 0

Question 6:  If phi =1/(r^2)   then (delta)^2  phi is

a) 1                         b) -1                c) 0          d)1/(r^2)

Question 7:   If f(x,y)=1 throughout the region D then I=integral integral dx dy represents

a) Volume   b) Arc        C)  bounded below          d) bounded above

Question 8 :    If function fxx(x0,y0)=0 then f has a -----  at (X0,y0)

a) relative minima        b ) relative maxima   c) saddle point

Question 9 :   The angle between Vectors   -2i+3j+k  and i+2j-4k is

a) 0 degree           b)  90 degree    c) 180 degree

## #6 Exercises » Calculus MCQS IMPORTANT » 2019-12-29 07:22:54

Zeeshan 01
Replies: 1

Question1 : if the function fxx(x0,y0)>0 then f has a ------ at (x0,y0)

a) Relative minima     b) relative maxima  c) saddle point    d) none

Question2 : if phi=2xz^4-  (x^2y) , the |delta phi | at point (2,2,-1) is

a) 2sqrt93     b) sqrt 372  c) 2sqrt91    d) both a and b

Question 3 : if y=f(x) has continuous derivatives on [a,b] and s denotes the length of arc between the lines x a and x  b then

Question 4 :  arc length s=integral a to b   sqrt(r^2+(dr/d thetha)^2 ) d thetha is called

a) Rectangular Coordinates   b)  polar coordinates   c ) spherical coordinates   d) none

Question 5 : if the two vectors are A=3i+4j+k   and B=i-j+k then

a)They are orthogonal   b) orthonormal   c) antiparallel   d) none

## #7 Help Me ! » MCQS (Linear Algebra) » 2019-06-06 18:55:47

Zeeshan 01
Replies: 1

Question 1 :Evaluate i.jxk

Question 2 : The component of the curl of a vector field F=Mi+Nj at (x,y) is

Question 4: If  A B and C are the matrices of order 2x2 and AB =AC then
1) B=C   2)A=B    3) A=C    4) None

Question 5 : Curl (grad f ) is
A) f  B) delta(rounded)  C)  0   D) None

Question 6 : If  2A+b=[1  2     and 3A+2B = [10   15    then  A and B is ?
3 5 ]                         22  23

Question 7 : If pi (x,y,z) =3(x^2)y  - (y^2) * (z^2)    then delta(rounded) pi  at the point (1,-2,-1) is

## #8 Re: Help Me ! » Probability Distribution » 2019-05-24 06:08:36

Construct the probability distribution for the no of break downs from the following data.

Check the question Again.

## #9 Help Me ! » Probability Distribution » 2019-05-18 19:29:27

Zeeshan 01
Replies: 2

Q)   In the following frequency distribution 'x' shows the number of machine breakdowns and 'f'  shows the frequency of occurrence of 'x'.Construct the probability distribution for the no of break downs from the following data.
x    0  1  2    3    4   5   6  7  8  9
f     5  8  9  11  14  10  7  4  3  1

Also find probability
1)  X>6
2)  X<3
3)  X>7

## #11 Re: Help Me ! » Probability » 2019-05-07 01:07:40

How many breakdowns occur in total?

f     5  8  9  11  14  10  7  4  3  1

By Sum Of frequency =72

## #13 Re: Help Me ! » Probability » 2019-05-02 19:47:18

zetafunc   wrote:

For part b, calculate how many breakdowns occur in total. How can you use this to calculate, say, the probability that no breakdowns occur?

Solve this .

## #14 Re: Help Me ! » Probability (3) » 2019-05-02 19:45:42

Question : Four coins are tossed simultaneously . What is  the probability distribution for number of heads.

HHHH      THHH

HHHT      THHT

HHTH      THTH

HHTT      THTT

HTHH      TTHH

HTHT      TTHT

HTTH      TTTH

HTTT       TTTT

0                1                                       1/16 = 0.0625

1                4                                       4/16 = 1/4 = 0.25

2                6                                      6/16 = 3/8 = 0.375

3                4                                      4/16 = 1/4 = 0.25

4                1                                      1/16 = 0.0625

## #15 Re: Help Me ! » Probability MCQ » 2019-05-02 18:56:42

ganesh wrote:

#1 It is better to see this  https://www.quora.com/What-is-the-probability-of-selecting-a-black-card-or-a-6-from-a-deck-of-52-cards

Q.2 Total male and female = 25+15=40  so The Probability for selecting female  = 15/40

Q.3 sample space (1,1)     (1,2)    (1,3)    (1,4)    (1,5)    (1,6)
(2,1)    (2,2)    (2,3)    (2,4)    (2,5)    (2,6)
(3,1)    (3,2)    (3,3)    (3,4)    (3,5)    (3,6)
(4,1)    (4,2)    (4,3)    (4,4)    (4,5)    (4,6)
(5,1)    (5,2)    (5,3)    (5,4)    (5,5)    (5,6)
(6,1)    (6,2)    (6,3)    (6,4)    (6,5)    (6,6)
from sample you can see by adding numbers if it equals to 12 .  that is only one possibility (6,6)   so probability is 1/total

Q.5
The sample space S (which is the set of all possible outcomes) is listed below:

S = {1,2,3,4,5,6}.  so greater than equals to  3 is    3, 4, 5 , 6 so probability is 4/6 or 2/3.

This is real explaination.

## #16 Re: Coder's Corner » Technical Coding » 2019-03-21 07:02:54

Anyone there to solve this problem by program?.

C ++ language.

## #18 Coder's Corner » Technical Coding » 2019-03-16 00:27:46

Zeeshan 01
Replies: 3

Different Type of Problem

Write a program that compose message in the same fashion as using mobile keypad. The program must receive integer input. When use enter 2 the program outputs letter ‘A’ and if 2 is pressed twice, the letter ‘A’ will disappear from screen and character ‘B’ will appear and if 2 is pressed thrice the letter ‘B’ will disappear and Letter C will appear. To enter ‘AA’ you have to enter number ‘2’ twice with delay. Delay must be as smaller as it is usually in the mobile.

To check a delay between two key press use the following library

#include <time.h>

To get the current time use following function

time(0)

This function will return numeric value of time. You can compute the time difference by getting time at both key press events and test for a fixed time delay to check whether the key press are consecutive or not.

If you want to clear screen use following statement

System(“CLS”);

Similarly find the associated letters with numbers

Requirement.
You cannot use string and character array. Only primitive data types are allowed. You are allowed to use header files that is mentioned or may use other libraries.

## #19 Exercises » Calculating Quartiles » 2019-03-11 07:06:40

Zeeshan 01
Replies: 2

Find Quartiles for Ungrouped data         // Exercising this type of questions
The ordered observations 84.60,88.03,94.50,94.90,95.05

n=5

Q1=(n+1)/4 observation ie 1.5th observation

so Q1=84.60+0.5(88.03-84.60)    // Why use this formula and what is 1.5th observation and what is formula when ans is 1.75 , 1.06 etc

Q1= 86.315

Q3=3(n+1)/4
= 4.5 observation

so, Q3 = 94.90+0.5(95.05-94.50)   // this calculation changed from above

so Q3= 95.175

## #21 Maths Is Fun - Suggestions and Comments » Suggestion » 2019-02-25 06:20:31

Zeeshan 01
Replies: 2

Hi;
Math is fun is missing some important things that is Echelon Form and column operations, row operations.

Math is Fun must include these core topics as it is compulsory as soon as possible.

## #22 Help Me ! » Last step » 2019-01-27 02:15:03

Zeeshan 01
Replies: 2

Finding point of inflection
Fx= 2/x-4/x^2
I take second derivative tesr that is
4(x-6)/x^4
And point of inflection is 6 but in book there is two point of inflection 2/9 ,6

## #23 Exercises » Integration » 2019-01-17 16:56:36

Zeeshan 01
Replies: 5

Exercising this type of integration questions
Q. integral from 0 to pi\4 ln(1+tanx)

Zeeshan 01
Replies: 0

Solved

## #25 Exercises » Derivative » 2019-01-13 04:45:38

Zeeshan 01
Replies: 1

F(x)=e^x * cos (x-a)
Want to exercise this type of question
Know simple derivation but want to get this answer that is
Derivative=re^x cos(x-a+thetha)
R=sqrt 2 thetha=pi/4