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adding feet and inches on a regular calculator
5

adding feet and inches on a regular calculator

adding feet and inches on a regular calculator

2
(OP)
I have been using this method of adding feet and inches on a regular calculator for several years.  I just recently stumbled on a write-up of the method.  If you work in feet and inches, this is a very helpful method.

RE: adding feet and inches on a regular calculator

Interesting. Yet another reason to use Metric in preference to Imperial measurements!
  

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If we learn from our mistakes I'm getting a great education!
 

RE: adding feet and inches on a regular calculator

works untill you add more than 100 inches together

why not "just" add the inches together (getting a result in feet and inches (98" = 8'2") then add the feet together ?

RE: adding feet and inches on a regular calculator

"Interesting. Yet another reason to use Metric in preference to Imperial measurements!"

Yeah, and in the US there are about a thousand other reasons for not using the Metric System, like that it is more expensive, less available, and is a general pain-in-the-ass.

The Metric System is overrated anyway.

Don
 

RE: adding feet and inches on a regular calculator

My calculator does fractions.  1 inch = 1/12 of a foot.

RE: adding feet and inches on a regular calculator

What a way to complicate something so simple.

What's wrong with entering say, 18+5/12+2+7+2/12+5.5?  Is it that hard to do?  You can just punch it into the calculator like that.

And, sadly, the metric systems have their own little quirks, but that's a different story.

RE: adding feet and inches on a regular calculator

There are plenty of calculators that do fractions.  Mathcad does fractions.

The cited approach is rife with potential errors, particularly in taking differences of measurements.

TTFN

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RE: adding feet and inches on a regular calculator

jstephen, what quirks? Other than the fact that here I am 182cm tall and 182pounds (systems mixture in Canada)

<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying " Damn that was fun!" - Unknown>>

RE: adding feet and inches on a regular calculator

unotec-

So do you weigh 83 kg or 810 N?

What's the pressure in your water system? Would that be in Pa, kg/mm^2, bar?

And, as I like to point out... I'm still waiting for "metric time". I can understand 365 days per year since that is based on natural planetary issues. But who dreamed up this 24 hours / 60 minutes / 60 seconds business anyway? If the metric folks were thorough, we'd have 10 decidays in a day, with one deciday equal to 2.4 hours, or 100 centidays in a day with one centiday equal to 14.4 minutes... Guess we'd have to totally redo Newtons and thus Pascals also...

jt

RE: adding feet and inches on a regular calculator

Oooh man!  Then life would REALLY be easy!

Don
Kansas City

RE: adding feet and inches on a regular calculator

jte, that is different units in the same system on the same 100basis.

To me that is much simpler than a 12 or 16 basis (I'm not very smart, so I rather divide by 10 rather than 12)

However, time.... well, as far as I am concerned the aztecs were the only ones that had it right.

BTW, I pay for litres (liters?) of water but it comes at psi's

<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying " Damn that was fun!" - Unknown>>

RE: adding feet and inches on a regular calculator

Little quirks- most of us in the US learned the SI system in school, only to find that in the real world, "metric" does not mean "SI".  So, for example, I find everyone talking about pressures in bars, and that never even came up when we were doing "metric" stuff.  And then I see mill test reports, and they'll show yield strength in kgf/cm^2.  Logically, the standard of volume would be cube of the standard of length, but it's not- it's off by 1,000.  Logically, the base unit of mass would be the mass of water in a cubic unit- but it's off by 1,000,000.  Or the mass of water in a standard volume, but that's off by 1,000.

Arbitrarily choosing the standard of length as 1/10,000,000th of the distance from equator to pole unfortunately does not simplify much in the way of calculation.  Setting the units so that a unit mass weighed a unit force, and consisted of a unit cube of water would have been a much better start to it all.

If you'll take that original problem, and look at the metric equivalents, you don't really solve anything.  If you need to add meters and fractions of meters, you have exactly the same problem you do in feet, and wind up just converting everything to decimals and adding.  On the few metric engineering drawings I've seen, they handled this issue by just showing every dimension in millimeters, regardless of how big it was, which is not an overly convenient system, either.  In that case, the original problem becomes 5613+610+2184+1676, which is not too convenient for adding in ones head.

RE: adding feet and inches on a regular calculator

JStephen is right.  In the engineering world, we do calculations with real numbers with calculators.  The fact that a system is based on powers of ten doesn't really help much.

The reason the United States hasn't fully converted to the Metric System is simple:

It costs more than its worth.

If metric fasteners, parts, gauges and tools were just as easy and cheap to get as ordinary ones, and if using metric units caused some sort of significant savings in time or accuracy (and therefore money), it would justify its cost and any American company would have jumped all over it long ago.  The fact is, it doesn't and it's simply overrated.  

As all American engineers, I am 100% bilingual and fluent in both systems (which is more than can usually be said for those in other countries) and have been since fifth grade (1975).  I calculate in both systems every day.  Both of them are childishly easy to work with.  

Unless it contributes to the bottom line, rather than just to anal-retentive sensibilities, it's going to be a little while longer until the US slowly adopts the Metric System.

Don
Kansas City

RE: adding feet and inches on a regular calculator

So Liberia, Burma and the USA are right and the rest of the world is wrong then?

RE: adding feet and inches on a regular calculator

I think it's likely that the US will gradually become more metricated as indigenous manufacturing declines and more products are imported from the East where metric is the norm. Metrication by stealth!
  

----------------------------------
  
If we learn from our mistakes I'm getting a great education!
 

RE: adding feet and inches on a regular calculator

Liberia, Burma (I'll assume you mean Myranmar), and the U.S. huh?  I'm in Auckland this weekend and took a tour yesterday.  The bus had 30 people on it and only 4 were from those countries.  The initial anouncement was "we'll be traveling 360 miles today and should expect temperatures around 75F".  As I recall, New Zealand went Metric over 50 years ago so the bus driver never lived under the imperial system.  The first metric word out of his mouth was an hour into the drive he started translating speed limit signs for us.

At the hot springs the temperature of the mud pots was given by a native guide as "208F which is somewhere around 85C (sic)".  She got the Farhenheit part right, but the translation was a bit garbled.

I'm reviewing the engineering specs for a job in Queensland, AU next week and most of the specifications were called out in DN numbers, but many of the lengths were in feet and the elevations were often in feet and inches.  Volumes are always in MMCF (which is a bastardization of the Imperial system for pity sake, it means "million standard cubic feet", the "M" is the roman numeral for 1,000, so it is a thousand thousand") or bbl (for 42 gallon barrel)--never a mention of a cubic meter.

People cling to convenient units.  80F feels warmer than 17C.  360 miles seems to roll off the tounge easier than 600 km.  None of the real SI pressure units are terribly convenient so people use a bastardized unit like kgf/m^2 to get to numbers they can process and still feel like they're "metric", psi would have been way better.

David

RE: adding feet and inches on a regular calculator

Most of the metric/imperial argument is pretty sterile.  I think there are justa couple of places where imperial conventions can put you at a disadvantage:

1.  The habit of using fractions of an inch for meausurements - not wrong in itself, but makes ordering much less obvious.  I have to think about whether 5/8 is bigger than 19/32 and I'd rather not have to bother.

2.  On the face of, having irregular subdivisions between units is a nuisance.  12 inches to a foot, three of them to a yard, and 1762 of them to a mile just makes for calculating errors, especially when different quantities require you to memorise different systems of subdivision (16:14:120:20, or 4:1:12:20 or 60:60:24:365ish). In real life, this is a problem best dealt with by ignoring it, which is why aviators simply work in thousands of feet.(perhaps the Brits' conversion to metric is just a different reaction to the mess which is 11St,11Lb:  Instead of adopting the american 165 Lb. we went for 75 kg).  As others have already pointed out, the metric world isn't entirely free of these strange conversions, but there are refreshingly fewer of them.

A.

RE: adding feet and inches on a regular calculator

Let's not forget that fathoms per fortnight is also a valid measure of speed. And all the others units / mixtures of units. I still fight the notion that folks in my industry have to state the quantity of pressure as simply "pounds." As in "The safety relief valve is set for 50 pounds." Now, I know they mean psi, but I usually ask them to clarify whether they are referring to the force required to move the mechanism or if they're referring to the process.

But I'm really responding to zeusfaber who says that aviators work in thousands of feet... So what exactly does a pilot mean when he says he's at "flight level 3000." Maybe we can do metric-feet here: decafeet!

jt

RE: adding feet and inches on a regular calculator

The US is in fact well along on metrification.  All the cars and many of the consumer products you buy are all metric, regardless of where they were made, for example.

The advantage to the US in going metric is not in using a simpler system, but in using a system consistent with the rest of the world.  If the US used the metric system and the rest of the world used a single specific non-metric system, we'd probably be switching the other way right now.

RE: adding feet and inches on a regular calculator

99% of peoples' daily contact with either system is not based on ANY unit of measurement;  they select a size based on visual cues.  Everyone (just about) has a foot to compare to.  Any housewife can select a container of milk by looking at it, without a care for its stated volume. That IMO is what makes the Imperial/US systems so enduring -- it just doesn't matter.   

RE: adding feet and inches on a regular calculator

JTE,

If an aviator says he's at FL3000, something has gone horribly wrong - that puts hima about five times higher than concorde ever flew.

Flight levels isn't really a height measure anyway - it's all about flying at a constant ambient pressure (so on a day when the barometer is reading a bit high, all the jets flying airways are that bit further away from the ground too).  Once you get into the business of genuinely wanting to know how close the ground is (perhaps so you can bomb, avoid, or land on it), everyone turns back to feet or, if the numbers are getting big, thousands of feet.

A.

RE: adding feet and inches on a regular calculator

@David : "80F feels warmer than 17C."
Well that's because it is!  80F = 26.7Cthumbsup

RE: adding feet and inches on a regular calculator

Returning to the original post.

I agree with the comments that this looks like a simple problem turned into a complicated process.  People carry out complicated processes with zero idea as to what they are really doing and why (e.g. school kids using log tables).
 

- Steve

RE: adding feet and inches on a regular calculator

by the way: kgf/m^2 is not a metric unit. It is and old unit and it should be Pascal (which in term is N/m^2).

Personally, living in Hollang I favor metric because it is easier (and more logical) to use steps of ten than twelve.
And over here in Europe, we have the idea that the US stopped promoting the use if SI units after the blew a satellite because of a unit mistake. Don't know if that is the real reason of course..

RE: adding feet and inches on a regular calculator

I say use nautical miles for distance.  They make all sorts of aviation type calculations easy to do you in your head.

A nautical mile is darn near 6000 feet.  So a Knot is 6000 feet/hr, which is easily converted in your head to 100 feet/min, and as rate of climb is usually in ft/min your L/D is also easy to do in your head.

RE: adding feet and inches on a regular calculator

This is what I'm talking about.  Every time someone tries to tout the Metric System, or their own personal favorite, they give an asinine example of an "engineering problem" that involves simple, round integers that are nonchalantly converted in one's head.  This is ridiculous in the real world, since we almost always deal with crazy real numbers that have to be dealt with using a calculator anyway.

Don
Kansas City

RE: adding feet and inches on a regular calculator

let's not forget the US "imperial" units ... the US gallon (=3.8lt instead of 4.54 for the "full" imp. gallon), the short ton (= 2000 lbs, maybe 'cause they couldn't work with 2240 lbs ?) ...

byw zeusfaber, 1 mile = 1760yds = 5280ft

napoleon (ok, maybe republican france) tried "metric" time ... we're fixed to 365.25 days per year (but can have 10 months) and a day is a fixed length (but we can fudge with the hours/minutes/seconds, maybe 10 hours,100 minutes, 100 seconds).

RE: adding feet and inches on a regular calculator

kgf/cm^2 is a "metric" unit, it just isn't a standard SI unit.  Similar to dynes, bars, poises, and whatever other dimensional oddities are floating around out there in the real world.

RE: adding feet and inches on a regular calculator

I stand corrected..

RE: adding feet and inches on a regular calculator

As do I.

A.

RE: adding feet and inches on a regular calculator

kgf/cm^2 may be thought of as a metric unit, but it's a bad one, with an arbitrary nasty constant thrown in (based on Earth's gravitation field).

- Steve

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