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Happy to help!

Assuming it was solving before (with 50,000) as the initial amount and not complaining of non-linearity, simply changing the initial 50K to 100K should not be generating this issue. Therefore, it's some sort of bug. I've seen these before with Solver. Sometimes, clicking (or un-clicking) the box that says "Automatic scaling" in the Solver options takes care of this.

@@TallysYunes Thanks! I suppose another way around it would be to convert the initial amount to thousands of dollars, so 100 in my case. This solves fine.

Yes, indeed. Sometimes if you scale the numbers yourself so that the difference between the smallest and the largest number in the data is reduced, this kind of bug goes away. Good thinking!

If by "two plants" you mean two different products whose inventories have to be tracked, you can simply duplicate the variables and repeat the same set of constraints for each product individually.

@@TallysYunes It's more transshipment in my case. Solver cannot find a solution.

Check out the transshipment example on my playlist (if you haven't yet) and double check that all your constraint formulas are correct. If it can't find a solution, there's at least one constraint that is being too strict.

This problem has alternative optimal solutions. As long as you still get 22.333 in cell H16 and all the constraints are satisfied, you're fine.

@@TallysYunes thank you!

This is caused by the problem being over constrained and the issue is with one of the (or a group of the) constraints. What I usually do is this: go to the grey area (i.e. the variables), start with it empty, and then assign some simple values to the grey cells (for example 1 or 2) and check that the resulting calculations that use those cells are returning the values you'd expect to see. Or try inputting a solution that you know should be feasible and then see if some calculated number looks weird. For instance, in this problem, type in the gray area a solution that only makes one type of gasoline. Try this with all gasolines (one at a time). You'll eventually find out where the issue is. In the worst case, go back to the beginning of the video and double check that all the formulas you are typing match mine exactly. Good luck!

What are the 3 parameters of this triangular distribution?

Essentially I’m trying to model future growth in an industrial company that has historically (15 years data) varied from -2% to +8% with median at 3%.

If the triangular function doesn't allow you to enter a negative for the low end, you can shift everything up 2% points and subtract afterward. For example: Cell A = randtriangular(0, 0.05, 0.1), and B = A - 0.02. This will make cell B behave as if it were a randtriangular(-0.02, 0.03, 0.08).

@@TallysYunes Thanks, Prof! Will try this.🙏

You're welcome!

I can't do homework for you, but it's likely that the one you need to tackle is similar to one of the examples in my videos. Look through my Excel Models playlist.

@@TallysYunes of course not! I'll be sure to check out the videos. I'm struggling with determining if it's blending or allocation, and determining the inequalities for blending. Especially when there's multiple rates and units of measurement. Do you offer tutoring?

At the moment I don't have time for one-on-one tutoring, but this is something your teacher would be able to clarify for you (it's their job). Have you tried reaching out to them? Do they offer office hours?

Thank you! I'm glad the videos are helping. Yes, you can add an "int" constraint on the gray cells. I don't do it in this video because I use this example to illustrate the ideas I go over at the end of the video to my students.

@@TallysYunes Can I ask what book you recommend? I see a few popular recommendations online. What would you choose?

Here's one that I like: www.amazon.com/Spreadsheet-Modeling-Decision-Analysis-Introduction/dp/130594741X

I don't have a detailed video on that, but at the beginning of this video I show you the mathematical formulation and the setup of the Solver window (you can pause the video at that moment and look at what I did). The formulas in column F and in cell B12 are all the same: a SUMPRODUCT. If you watch and understand the Farmer Problem example I have on this channel, you should be able to do this one.

In this case, you can deal with it as if it were two separate statements and it will result in two constraints: a) If we advertise on 3, we must also advertise on 9. b) if we advertise on 3, we must also advertise on 10. You can do each of the above with the "if this then that" formula that the video teaches.

You're welcome!

Thank you!

Thank you! There may be, but I'm not aware of any native Monte Carlo facilities for Excel other than the brute force way that can become very time consuming.

You're welcome!

Awesome! Thank you!

You're welcome.

Thank you! I'm happy to hear it helped!

I meant great playlist, not just this video. Doing a marathon of the playlist now :)

Thank you! And you're welcome. I'm happy to hear the video was helpful.

Great to hear!

Thank you!

You're welcome!

My pleasure!

You're welcome! Glad it helped!

Thank you so much!

You're welcome!

I'm not a finance person, so I'm going to need you to give me a thorough explanation of what you're trying to do exactly. Beginning with the definitions of "long-term debt" and "DCF Analysis." Haha!

If I understand your question correctly, you replace the symbol >= with = so that exactly 1 neighborhood is chosen and all the other adjacent ones can't be chosen.

@@TallysYunes oh Thank you, if change the equality sign from>= to = it is not providing any solution to me :(

for example, one of the solutions can be neighbourhoods 1,8,6 as these are not adjacent neighbourhoods and at the same tile 1,8,6 cover all their adjacent neighbourhoods too, that is basically what my question is to choose neighbourhoods to place fire station that are not adjacent to each other but at the same time cover all neighbourhoods too, i hope you understand my question

Ah, OK. NOW I understand what you were asking. Then bring all the original constraints back to >= 1 and, for every pair of neighborhoods that are adjacent, add a new constraint saying at most one of them can be = 1. So for example, because 1 and 2 are adjacent, you add the constraint x1 + x2 <= 1. Repeat for every pair of adjacent neighborhoods. There will be lots of these.

Think about each kind of resource separately. A product can consume a certain amount of man hours and a certain amount of machine hours. So your constraints could be: (man hours consumed) <= (man hours available) (machine hours consumed) <= (machine hours available) The latter constraint could be one per week (if your variables are products produced per week) or a single one for the entire operation. Without seeing more details of the problem, it's hard to tell. At the moment, I don't have a specific video of an example that's similar to what you describe. But this is a good idea for a future video.

Haha! Thank you! I'm happy to hear you enjoyed it! I'm on season 6 now but haven't found another case yet where optimization could help. But this was a fun video to make.

Yes ofcourse! also i wanted to ask if you do not mind all the questions that you cover in the playlist are covered by my optimization professor so was wondering what textbook or reference do you use to get these questions so that i can practice more with similar questions?@@TallysYunes

The videos in my "Excel Models" playlist go over the examples I cover in my intro to optimization class that I teach at the Undergrad/Masters/MBA level. I followed the book by Cliff Ragsdale entitled "Spreadsheet Modeling and Decision Analysis" until 2019 (been using my own notes since then). If you're looking for additional practice problems on these topics, this book is a great source of examples. You can get a used 7th edition of this book on Amazon for very little money.

🤣 The point of the video is explained within the first 2 minutes. 🤣

Thank you! I'm happy to hear the video has been helpful.

Thank you!

You're welcome!

same

I agree! Glad you liked it!

You're welcome!

You're very welcome!

Take a look at my "Excel Models" playlist. There's a good chance the one you're trying to solve is similar to a problem I address in there.

Thank you!

​@@TallysYunes Can you videos about: MILP to solve Job Shoo scheduling problem using excel. Like this one: www.ijmer.com/papers/Vol7_issue3/Version-2/D7322329.pdf I really hope you can do 👌🙏

If these are costs per unit produced (rather than fixed costs), they can be added to the costs of the arcs that depart from the plant.

Hello Sir, please make a video about this: drive.google.com/file/d/1QLdiRT3rzqgYntI6sJy5SOmhFCqUaTWf/view?usp=sharing but using Excel not Lingo! @@TallysYunes

I hope you can do that sir🙏