Comments on: I am NOT a math guy – so help! :)

By: Paul Claessen

Paul Claessen — Mon, 02 Apr 2007 18:39:15 +0000

@Kami .. That they are different units is NOT a (the!) problem in this case, since you can express one unit as a fraction of the other, so, in essence, you only have one unit (dimension). And even when you express the cents in dollars ($0.01) you STILL end up with an incorrect formula.
But you’re right about the other part of your comment: the problem is in the squaring. That stated equality “100c = (10c)^2″ is, in fact NOT an equality. (10c)^2 is NOT 100c. It is 100(c^2). Of course, I don’t know what a square cent is, but that doesn’t mean you can simply ignore it. The human brain is extremely good at ignoring ‘non-sensical’ data and/or replacing it with something it DOES know, but in math, you can’t do that! 10c * 10 = 100c. 10c * 10c = 100(c^2), something different altogether.

By: Kami Huyse

Kami Huyse — Mon, 02 Apr 2007 17:14:48 +0000

@Paul: I am late to this party, but it is wrong because cents and dollars are different units, you cannot square one of then to get the other. Common sense again.

By: Paul Claessen

Paul Claessen — Mon, 02 Apr 2007 14:02:59 +0000

@David .. correct formula (I don’t have a son, so I used wikipedia instead). And if you try to calculate this in Excel (like I did) the formula is =TAN(20*(PI()/180)) (since Excel insists on the angle being in radians, rather than degrees).

As for the ‘money’ formula you gave:
1. It doesn’t tell me what was wrong with mine!
2. It is wrong too!

By: david

david — Mon, 02 Apr 2007 05:08:14 +0000

Actually, I compensated for the 4 inches. I just needed help on the formula to figure out the sides of a triangle (long time since I did that math). So the formula according to my son was tang(angle) = opposite/adjecent.

(10Ã‚Â¢)^2 = ($0.10 * 10^2)^2

By: Paul Claessen

Paul Claessen — Mon, 02 Apr 2007 03:00:43 +0000

@David… re: comment #22.

This comment has me stumped.
For several reasons.
First of all: why that calculation? You already established that the slope plays no role whatsoever.
second: How can you get the slope on the wrong side? I gave the shallowest point, and said it was length-wise.
third: you need your son’s help with this?
fourth: I’m VERY impressed by your son’s trig AND arithmetic (to compensate for the 4 inches!) skills!

So… now… go for the bonus points! Answer comment 18 (19)

By: Paul Claessen

Paul Claessen — Mon, 02 Apr 2007 01:50:03 +0000

@david … re.: comment #21:

“..you would have the same amount of water ..”

Absolutely correct! No bonus points though, since Rob already answered this correctly in comment #11, and I acknowledged his correct solution to my weak attempt at an April-fools-day math problem in comment #12.

By: David

David — Mon, 02 Apr 2007 01:40:04 +0000

Of course at a 20 degree decline the deepest part is only around 14.9 feet… Unless I have the 20 degrees on the wrong side then it turns to around 13.86 feet…

(all done with help from my son… )

By: David

David — Mon, 02 Apr 2007 01:14:38 +0000

Paul,

When you say that the shallowest part of the pool is 4 inches you are talking about the pool going from 4 degrees deep to the deep in it would seem that you still have the same 38×22 foot catch basin to receive rain water… thus you would have the same amount of water in the bottom of the pool.

David

By: Paul Claessen

Paul Claessen — Sat, 31 Mar 2007 21:19:00 +0000

Oh, and that’s 10 bonus points for ANYONE who gives the first correct answer!

By: Paul Claessen

Paul Claessen — Sat, 31 Mar 2007 20:37:53 +0000

Besides, that post deserves AT LEAST 20 comments!

By: Paul Claessen

Paul Claessen — Sat, 31 Mar 2007 20:37:09 +0000

No! Can’t leave it alone yet.
I STILL need Rob to do a little thinking.
This time with regards to my proof that $1 = 1 cent.
It SHOULD be fairly easy, since I already explained WHAT KIND of error he made with the volume, and as EXAMPLE of the SAME error I presented my proof that $1 = 1 cent.
So here’s the question: Since common sense dictates that $1 is NOT equal to 1 cent, WHERE in the given formula lies the error?
(10 bonus points for this one)

By: rob

rob — Sat, 31 Mar 2007 20:34:48 +0000

Actually – good point. But no dice – we are just finishing the wettest March in recorded history here – we had at least four days that gave us at least 3 inches of rain (the real long rainfuls that actually help the Edward’s Aquifer). Of course, those rains also mean flooding, and we’ve had a bit of that.

By: Dawnell

Dawnell — Sat, 31 Mar 2007 20:25:11 +0000

QUIT worrying about this! By now I am sure all the water in Rob’s pool has dried up, anyway!

By: Paul Claessen

Paul Claessen — Sat, 31 Mar 2007 19:07:02 +0000

Well, knowing the person in question, since the claim was so outlandish, I guess it was his way of telling you you weren’t going to get it. Period.

By: rob

rob — Sat, 31 Mar 2007 19:04:27 +0000

Yes. That’s what he said. And it pre-dates Cheney’s adventure by several years

By: Paul Claessen

Paul Claessen — Sat, 31 Mar 2007 19:02:21 +0000

About lying about lost source …

There are probably one or two source files out there that I gladly (but wrongly) would deny authorship of.
(There are more instances where I deliberately have removed my name from source code, but that had more to do with contributions by others

And although I despise lying, if I HAD to lie about losing source code, I most DEFINITELY wouldn’t try making people believe that I lost it in “A HUNTING ACCIDENT”!!

A disk crash… sure… but A HUNTING ACCIDENT? Did I read that right?

By: Paul Claessen

Paul Claessen — Sat, 31 Mar 2007 18:32:53 +0000

On one hand I’m glad to see you still know when NOT to apply math … just common sense.

On the other hand .. I’d SOOO hoped you would spend the rest of the weekend trying to figure this one out…

By: rob

rob — Sat, 31 Mar 2007 18:29:30 +0000

@Paul – the answer is the same – he slope doesn’t matter in this case because we are measure the volume of water trapped over a given area – the slope doesn’t come into play.

By: rob

rob — Sat, 31 Mar 2007 18:28:17 +0000

This whole thread reminds me of re-writing Trent’s PRISM Benchmark program (I relaunched it as PRISM Benchmark Pro).

I saw numbers with his tool that didn’t make sense to me – so I asked him for the source. He told me it had been lost in a horrible hunting accident. So I re-wrote the application from scratch. About a year later I found the source on Trent’s lab server (so he lied to me, and two years later when he worked for me – I remembered that lie )

Anyway, I took my souce to Allen and Wes so often to double-check my math that I know they were sick of seeing me. But now that thousands and thousands of people have used Benchmark Pro, I’m glad I took the extra precaution of getting quadruple-checked. THAT is how much faith I have in my math abilities

By: Paul Claessen

Paul Claessen — Sat, 31 Mar 2007 18:24:24 +0000

Okay, just to FORCE you to use your brain…
Same situation but now your pool’s bottom slopes 20 degrees lengthwise, with the shallowest part being 4 inches deep.

NOW what is the answer?
(You’ve got two minutes for this one…)