"Solver could not find a feasible solution"

[djhuckfield]

Hi everyone, I'm trying out Solver for the first time and it's not working as expected - hopefully someone will have some idea of what I'm doing wrong.

Below is screen print of my current layout, copied from a YouTube tutorial - I'm using Solver on cell M15, changing cells I5:I14, with constraints on cells I5:I14 and J5:J14 that they must be equal to or greater than zero. The result I'm trying to achieve in cell M15 is 56%. Every time I run it, I only get the error message that Solver cannot find a feasible solution - any ideas where I'm going wrong? I've shown the formulas I'm using in cells M5:M14 to the right of them.

 

[shg]

I'm using Solver on cell M15

M15 is empty in your picture.

 

[djhuckfield]

M15 is empty in your picture.

It's not empty, it says 53%, generated by the average function from the cells above...

 

[shg]

Ooh -- bad eyes!

Can you put a worbook on box.net and post a link?

 

[BadgerRoad]

First of all, shouldn't M15 be L15/K15 rather than the average of the percentages? If so, you get a solution.

 

[djhuckfield]

First of all, shouldn't M15 be L15/K15 rather than the average of the percentages? If so, you get a solution.

Ah - thanks, that seems to make it come to a solution. The only problem is it provides an answer of selling very few products, as shown in this image (ignore the AVERAGE formula I just forgot to delete the label, the actual formula is now L15/K15 as you suggested):

I'm using this tutorial: https://www.youtube.com/watch?v=K4QkLA3sT1o
(he runs the solver around 6:28) and his answers were much more what you'd expect a business to realistically want to come up with, but he didn't seem to use any more constraints than I did - any idea what would cause that?

 

[BadgerRoad]

I've looked at this video and I can't get his results either. His explanation of Solver is sound but I just don't see how he got his results. I also see things on his spreadsheet that don't make any sense. For example, on one screen he has a product costing $90 and he sold 24 but shows gross sales of $2187 instead of the correct answer of $2160. He also should have a constraint that makes the units to sell an integer. Again, I don't know how he got his results and would need a copy of his spreadsheet to analyze further.

 

[djhuckfield]

I've looked at this video and I can't get his results either. His explanation of Solver is sound but I just don't see how he got his results. I also see things on his spreadsheet that don't make any sense. For example, on one screen he has a product costing $90 and he sold 24 but shows gross sales of $2187 instead of the correct answer of $2160. He also should have a constraint that makes the units to sell an integer. Again, I don't know how he got his results and would need a copy of his spreadsheet to analyze further.

I guess I can add a few more constraints, maybe that units sold have to be above a certain amount or percentage - the important thing is I got Solver to work, so thanks everyone for your help!