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#101 Re: Exercises » Slope - Slope of Two Points » 2006-09-16 13:10:50
The formula for finding slope when two points are given is,
(The two points are (x1, y1) and (x2, y2).)
Slope = (y2-y1)/(x2-x1).
Using this formula, we can find the slope of the given points.
#102 Re: Help Me ! » Please Help » 2006-09-16 12:52:58
x=????????
#103 Re: Help Me ! » stuck » 2006-09-16 12:44:55
Hi,
This is the answer for your question.
Given that,
e^x = 5
Take log on both sides,
log (e^x) = log 5
We know that, log (e^x) = e^log x = x.
Therefore, x = log 5.
x = 0.6990. ( log 5 = 0.6990)
#104 Re: Help Me ! » Series of patterns » 2006-09-16 09:07:15
Hi..
This is the answer for your question...
Pattern number = N
The first figure = 2 grey and 2 white
The second figure = 3 grey and 4 white
The third figure = 4 grey and 6 white
Continuing this way, we will get
The N-th figure will be,
(N+1) number of white + 2N number of grey.
Therefore,
Expression for the number of grey tiles= 2N
Expression for the number of white tiles = N+1
The total number of tiles in the N th figure = N+1+ 2N = 3N + 1.
Hope you have understood the problem.
#105 Re: Help Me ! » Operation Research... I need help, Please help meeeeeeeeeeeee » 2006-08-09 09:00:46
What about the answer?
Can anyone help me?
Please....................
#106 Re: Help Me ! » Operation Research... I need help, Please help meeeeeeeeeeeee » 2006-08-04 11:51:53
Please, can anyone help meeeeeeeeeeeeee
Pretty pretty please.......................
#107 Re: Help Me ! » Help meeeeeeeeeeee.......... » 2006-08-04 11:50:38
Thanks a lot..................... 
#108 Help Me ! » Help meeeeeeeeeeee.......... » 2006-07-28 08:08:57
- Prakash Panneer
- Replies: 3
This is one of the operation research problem. PLEASE HELP ME.....................
A large computer store purchases a component used in the assembly of desk top computers directly from a supplier. The price of each component is RM8.00. The supplier will deliver order of any size for a charge of RM4.00. The cost of holding an item in inventory for a year is estimated to be 20% of the cost price. The store manager estimates that 500 components are required monthly. The store is open for 300 days a year. It takes approximately 10 days for an order to arrive once the order has been placed. Currently, the computer store has a policy of ordering 250 units, two times in a month.
1. Calculate the total annual inventory cost based on the current ordering policy
2. Compute the optimum order quantity and calculate the associated minimum total annual inventory cost.
3. Based on the optimum order quantity, should the store change its ordering policy?
4. Based on the optimum order quantity, determine the reorder point.
5. If the supplier offers large order discounts of 8% and 10% for single order quantities of above 400 and 500, respectively, should the company change its ordering policy?
Advance Thanks.........:)
#109 Help Me ! » Operation Research... I need help, Please help meeeeeeeeeeeee » 2006-07-28 07:21:46
- Prakash Panneer
- Replies: 4
Question 
Malik Carpets Sdn Bhd produces two popular grades of commercial carpeting among its many other products. In the coming production period, Malik has to decide how many rolls of each grade of commercial carpet to produce in order to maximize profit.
Each roll of Grade I carpet uses 50 units of synthetic fiber, requires 25 hours of production time, and needs 20 units of foam backing. Each roll of Grade II carpet uses 40 units of synthetic fiber, requires 28 hours of production time and needs 15 units of foam backing.
The profit per roll of Grade I carpet is RM200 and the profit per roll of Grade II carpet is RM160. In the coming production period, Malik has 3000 units of synthetic fiber available for use. Workers have been scheduled to provide at least 1800 hours of production time . The company has 1500 units of foam backing available for use.
The simplex method was used to solve the problem and the final simplex table is proved below.
Table:
C j Basic Variables $200.00 160 0 0 0 RHS
X1 X2 S1 S2 S3
200 X1 1 0.8 0.02 0 0 60
0 S2 0 8 -0.5 1 0 300
0 S3 0 -1 -0.4 0 1 300
Z j 200 160 4 0 0 12000
C j - Z j 0 0 -4 0 0
Sorry, I can't Draw a table Clearly. Can anyone help me?
...............................
1. Formulate the above as a Linear programming problem with the objective of maximizing profits.
2. Set up the initial simplex table for the above problem.
3. State the optimum output mix and the maximum profit attainable.
4. Are there any unused resource? If so state which and how much of the resource is not fully utilized?
5. What is the range of optimality for X1?
6. Determine the Range of Indifference for X2?
7. If Malik can obtain additional units of synthetic fiber for a premium of RM10 per unit, is it worthwhile for him to acquire additional synthetic fiber?
8. What will happen to the maximum profit and the output of Grade I rolls if Malik were to produce 30 rolls of the Grade II carpet. What is the implication of your answer?
9. Carry out a sensitivity analysis on the RHS value for the synthetic fiber constraint.
Advance thanks.
#110 Re: Help Me ! » Probability » 2006-07-11 05:41:18
Yes, draw the table.
#111 Re: Jokes » Airline Chatter » 2006-07-09 06:15:13
Nice one :-)
#112 Re: Maths Teaching Resources » Interactive Math Website » 2006-06-16 04:10:47
Superb..........:)
#113 Re: Maths Teaching Resources » Advanced Linear Algebra » 2006-06-16 03:58:08
Wonderful site.
#114 Help Me ! » Probability » 2006-06-15 10:33:07
- Prakash Panneer
- Replies: 3
Please help me................
Problem:
I pick two reals x and y. I show one of them to you randomly by tossing a fair coin. You have to tell me if the number you see is the larger or the smaller of the two. How do you do this so that for any choice of x and y, the probability that you are correct is strictly larger than .5?
ADVANCE THANKS..........
#115 Re: Help Me ! » Please help me. » 2006-06-07 02:11:38
:-) Many thanks for your help Ricky :-)
#116 Help Me ! » Please help me. » 2006-06-06 02:27:51
- Prakash Panneer
- Replies: 2
If R = {(1, 1), (2, 2), (1, 2), (2, 1), (3, 3)} and S = {(1, 1), (2, 2), (2, 3), (3, 2),
(3, 3)} are two relations in the set X = {1, 2, 3}, the incorrect statement is:
(A) R and S are both equivalence relations
(B) R∩S is an equivalence relations
(C)R^(-1)∩S^(-1) is an equivalence relations
(D) R∪ S is an equivalence relations
With Regarks,
Prakash Panneer
#117 Re: Maths Teaching Resources » Formulas » 2006-06-04 02:40:33
Hi duke1527,
This is a very useful site. Thank you so much.
#118 Re: Help Me ! » A integral problem » 2006-06-04 01:09:22
Oops....................
I made a mistake.
That means dv = e^(kx) dx
Integrating with respect to x on both sides, we get,
v = e^(kx)/k.
If y = e^(kx) then y' = k e^kx.
#119 Re: Help Me ! » A integral problem » 2006-06-01 08:56:02
You didn't give any information about j,k,and w. So, i took these are constants.
Problem: Integral ( t+1 ) e ^ ( -jwkt ) dt
To solve this problem, we have to use "Integration by parts method,"
Take u = t+1 , dv = e^ (-jwkt)dt
du = dt and v = e^(-jwkt)/(-jwk) (Oops)
Integrantion by parts formula Integral ( u dv) = uv- integral(vdu)
So, we will get, Integral ( t+1 ) e ^ ( -jwkt ) dt = {(t+1)e^(-jwkt) /(-jwk)} - Integral ( -e^(-jwkt)/(jwk)) dt
= {-(t+1)e^(-jwkt)/(jwk)} - e^ (-jwkt)/ (jwk)^2.
= {e^(-jwkt)/(jwk)} {-(t+1)- (1/jkw)}
This is our required answer.