Notifications
Clear all

Significant Digits TTT

6 Posts
5 Users
0 Reactions
2 Views
(@stephen-calder)
Posts: 465
Registered
Topic starter
 

#1 OK, guys, I had several categories unchecked in my profile that was preventing me from seeing the posts once I navigated away from the site. Now that's fixed thanks to a helpful email from Kent.

#2 This is an academic question. ACADEMIC. The first question was:
574.34' * 1.9' = 1,091.246' which according to the rules of Significant Digits, should be rounded to 1,100'. This seems fair and appropriate.

The second question concerns switching two of the digits as in:
547.34' * 1.9' = 1039.946'. By the rule of Significant Digits we have to constrain the answer to two digits. Is the answer...
1,040'? No. Three sign. digits.
1,000'? No. One sign. digit.
1,100'? Well, I guess, it has the right number of digits (Two), but, it seems odd to round up further for the correct answer than rounding down to 1,000'. And it seems odd that decreasing the quantity of the first number to be multiplied results in less precision in the result.

Butch, at least, seemed to get the point I was driving at, namely that following the rules of significant digits, which are UNIVERSAL rules (I didn't invent them, and they apply to any math calculations that involve approximate numbers), seems to lead to absurd results. He said:

"Applying the rule of sig figs to survey computations doesn't always provide meaningful data." and
"If the lesser measure could have been stated to the hundreth, the uncertainty changes by an order of magnitude, making it (uncertainty) much less consequential."

#3 Talk like a bitch; get slapped like a bitch.

Stephen

PS, Happy Thanksgiving

 
Posted : November 24, 2010 1:06 pm
(@adamsurveyor)
Posts: 1487
 

okay, nevermind. I will read the earlier thread before I post a response.

Advice: put the subject in before the letters TTT so everyone knows what subject you are bringing to the top.

 
Posted : November 24, 2010 2:58 pm
(@mlschumann)
Posts: 132
Registered
 

According to the rules, the correct result is 1000, not 1100, because 1039 rounds down. When a zero is significant, I was taught in junior high school, high school and college, to underline it. I'm sure others may have learned differing methods. In this case, the first zero right of 1 is significant and would be underlined. Another method, and this was presented in the original post, is to use scientific notation. 1.0 x 10^3 denotes two significant digits. If only one significant digit were to be specified, it would be written 1 x 10^3, and for 3, it would be 1.00 x 10^3. From a perspective of conveying important information, it doesn't matter which method is used. What is important is to state the number of significant digits to a reader or user of the presented information. I think just because I have learned some methods, I should assume others may have learned something completely different.

 
Posted : November 24, 2010 8:07 pm
(@kris-morgan)
Posts: 3876
 

TTT

I jump for cash bitch!

 
Posted : November 25, 2010 7:54 am
(@adamsurveyor)
Posts: 1487
 

TTT

> I jump for cash bitch!

You might tell the audience who you are responding to, otherwise it is a relatively stupid statement kind of floating in cyberspace. Kind of like saying TTT without saying what exactly you are bringing to the top.

 
Posted : November 29, 2010 7:05 am
Wendell
(@wendell)
Posts: 5782
Admin
 

Note: From the home page, if you click the "order" link just below the search bar, you can toggle between having the threads with the latest posts at the top (ordered based on the newest post in the thread, regardless of where it is in the thread) and the latest threads at the top (based on the date/time of the original post at the top of the thread).

 
Posted : November 29, 2010 7:36 am