Comments for sursumcorda.salemsattic.com/post/quick_tourists_conversion_between_fahrenheit_and_celsius

Comment #284

2014-01-22T12:08:36Z

You're welcome, John.

Comment #283

2014-01-21T23:29:20Z

Great. The wife is always bugging me but now I can do it in my head. Much thanks for this simple formula.

Comment #282

2013-10-11T10:30:11Z

Thanks, Wendy. They're not exact, but absolutely close enough for these purposes—and easy to remember.

Comment #281

2013-10-10T23:48:53Z

Another couple of good ones to remember are 61F = 16C and 82F = 28C.

Together with 50 = 10, you should be able to make an educated guess when trying to decide what the temperature is..

Enjoy!

Comment #280

2013-08-08T13:24:43Z

Thanks! Leaving for Australia next week and this is a hot tip! Gracias, gracias!

Comment #279

2013-05-14T09:45:06Z

Not unless you're asked for an estimate, Christa. Most math teachers want the exact answer.

Comment #278

2013-05-13T21:50:53Z

Will this work for my tests in math

Comment #277

2013-05-02T11:21:30Z

Why don't we just start using metric system - and Celsius - as any other good boy on this planet?? Easier and more effective...

Comment #276

2013-02-07T07:01:40Z

Really, the number of people who read this post but don't understand it at all is rather scary. What are schools teaching if so many people fail at such basic reading comprehension!

Comment #275

2013-02-06T21:34:35Z

Correct: the quick conversion is almost always wrong, but - and that's what matters - almost always close.

Comment #274

2013-02-06T15:54:35Z

try to convert using this formula

32 F to C

should be o C, but it comes 1 C

Comment #273

2013-01-15T11:18:45Z

This is great, easy to remember/figure out...

Comment #272

2012-12-31T04:49:59Z

Really helpful. Thank you

Comment #271

2012-09-28T12:01:38Z

You're welcome; I'm glad you like it.

Comment #270

2012-09-27T15:06:37Z

thank you for easy conversion method.

Comment #269

2012-08-18T18:20:47Z

Max's C° to F° forumla is 100% accurate, just a little less intimidating than multiplying with 9 and dividing by 5. His first formula, which is equivalent to dividing by 20 and multiplying by 11, means you get a result that is always exactly 1% too small, which for most people in most situations is more than sufficiently accurate.

Comment #268

2012-08-18T13:30:44Z

(More) accurate method is (For F to C)

Subtract 32

Devide by 2 (remember this)

Devide by 10 (add to the number above)

E.g

82-32=50

50 / 2 = 25

25/2 = 2.5

25+2.5 = 27.5

Other way around

Double the number (remember this)

Devide by 10 (Subtract this from the above)

Add 32

E.g.

15 * 2 = 30

30 / 10 = 3

30 - 3 + 32 = 59

Comment #267

2012-08-05T12:03:22Z

Welcome, Limeville. I do like your name!

Comment #266

2012-08-05T09:09:37Z

Thank you for the formula for F. I grew up thinking in Fahrenheit and, in these Centigrade/Celsius days, still do. I enjoyed your disclaimer. I have homeschooled and my grandmother's village is named for the limes that used to grow abundantly everywhere. Thanks again.

Comment #265

2012-07-13T19:17:59Z

Thanks for the quick tip! It's just I wanted!

I'm going to visit the Unites States next month and was looking for quick way to convert F to C.

Comment #264

2012-06-21T10:31:14Z

It is right, Natasha, if you add some parentheses: C = (F - 30) ÷ 2.

Comment #263

2012-06-20T17:19:24Z

Thanks, this is great! One suggestion to simplify the conversion formula for those visiting the United States (and I'm no mathematician, but think this is right): C = F - 30 ÷ 2 It’s just that some people don’t do very well with fractions.

Comment #262

2012-04-10T15:12:45Z

I hope you did all right on your physics test. This formula is only an approximation, and in my experience physics teachers tend to be a little pickier than that. It would be a good device for checking to be sure your answers make sense, though.

Comment #261

2012-04-10T11:56:37Z

Hey, this works I am in year 6 and I needed this formula to figure out my formulas quickly for my physics test

Comment #260

2012-04-01T22:46:47Z

You're welcome, Pat.

Comment #259

2012-03-31T17:40:37Z

I learned this quick calculation when I was in Australia last year. I remembered doubling the Celsius but forgot the number to add, and vice versa.

This answered my question quick and simple. And just in case I forget again, I have now Bookmarked this page for future reference.

Thanks so very much !!!

Comment #258

2011-10-27T05:02:03Z

Thanks so much! Goin to Japan soon and this will help

Comment #257

2011-10-23T10:19:28Z

Or, Lisa, you could go to www.weather.com or another weather website that allows you to switch between °F and °C. On that site, look up any city's forecast in °F, and convert to °C, then check your answers by switching to "metric". Pick another city, look up its forecast (now in °C), and convert to °F. Check your answers by switching back to °F. Repeat with more cities until you feel comfortable.

Comment #256

2011-10-22T10:56:09Z

Hi, Lisa! You don't want to use this method on a math test -- it is only an approximation, and teachers generally require exact answers. You could, I suppose, use the approximation to check to see if your answer, after doing the more complicated arithmetic, makes sense.

But you don't need worksheets to practice converting between Fahrenheit and Celsius. Using the exact formulas,

F = 9/5 x C + 32 and

C = 5/9 x (F - 32),

pick any number, use one formula to convert it, and then use the other to convert it back and thus check your answer.

I find that the real trick is in remembering the formulas. If I'm not sure (as I might not be under the pressure of a test), I check out my guess at the formula using values I know, such as the freezing and boiling points of water (32 F = 0 C, and 212 F = 100 C). Also, at -40 degrees, the Fahrenheit and Celsius values are equal.

I had no idea that math classes still required knowledge of this conversion. I'm impressed. :)

Comment #255

2011-10-22T02:07:54Z

I have a math test on Monday. we are using the method you provided. I cant find any math web pages containing practice work sheets with the formula. I really want to practice the conversions the way you've described. do you know where i can find some Q and A drills with this formula?

BTW I am going to school for the first time in 33 years and need all the help I can get with my math. Can you help?

Comment #254

2011-09-17T11:53:44Z

Glad you find it useful, Anne. Thanks for letting me know.

Comment #253

2011-09-16T14:09:44Z

Ah, thank you, just what I needed. I have a weather app on my Android that originated in Norway, and temps are only in Celcius.

I like this formula, nothing fancy, very quick and easy to remember.

Anne O, Philadelphia, PA

Comment #252

2011-07-21T10:12:31Z

Thanks, Martin. Certainly the formula you give is the correct and accurate one (as I noted above), and it is indeed easier to think of doubling and subtracting 10% than multiplying by 9/5. (Why didn't my elementary school teachers point that out?) But the point of my "quick conversion" formula is to give an approximation, not the exact value. For the purposes of deciding whether to wear a sweater or shorts, there is no difference between 80 degrees and 77.

Comment #251

2011-07-21T03:33:08Z

This method is Not correct!

To be more exact:

It should be

((Celsius X 2) - 10%) + 32

Eg 25F - 25 X2 = 50 - 5 + 32 = 77 Fahrenheit

Comment #250

2011-07-03T09:41:15Z

You're welcome!

Comment #249

2011-07-03T04:27:35Z

Terrific answer. Thank you. I learned this formula a few years ago, as a tourist in Australia.

Now, I'm making plans to go to travel Canada, and I think knowing this bit of information, will be helpful.

Thanks again,,,

Jim

Comment #248

2011-03-08T09:53:21Z

If your more familiar with Fahrenheit than celsius just remember the basics for celsius 15 and up you don't need a jacket, 5 and below you're gonna need a jacket, anywhere under -15 pull out your winter jacket haha

Comment #247

2011-01-08T13:02:53Z

Thanks, Memuna. I apologize for the long delay in moderating your comment; I quite neglected the blog over Christmas.

Comment #246

2010-12-29T22:53:09Z

This formula is superb. Even Kindergartens can use it conveniently. I like it thanks for the research

Comment #245

2010-11-19T12:42:14Z

The quick calculator only works well for the mid-range. That's why I said it's not good for tourists in Antarctica. :)

Comment #244

2010-11-18T14:39:32Z

what about if the temperature is -23C? what's the formula then?

Comment #243

2010-09-30T23:48:12Z

That's cool! I like the idea of remembering 50=10, too.

Comment #242

2010-09-30T23:17:08Z

Another easy one is that you picks temperature you know, the simplest being 0 C and 32 F (or 50=10), and knowing that adding 5 to the Celsius = adding 9 to the Fahrenheit, so if 32=0, 41=5, 50=10, 59=15, 68=20, 77=25, 86=30, 95=35, 104=40... and so on and so forth.

Comment #241

2010-05-23T15:38:46Z

Cool! A "good post" comment that's not spam. :) Thanks, Jon. I'm glad you found it helpful.

Comment #240

2010-05-23T11:32:45Z

Excellent. Very useful (and seems to impress as well!! LOL.

:) thank you

Comment #239

2009-06-30T20:44:53Z

That's a cool converter. I enjoyed seeing all those different units. What a pity, however, that my father's favorite speed measurement is not among them: furlongs/fortnight. It does have both furlongs and fortnights, however.

Comment #238

2009-06-26T10:18:01Z

I wish the government worked that precisely...

Anyway, for those who spend their vacations abroad online, here's a unit converter that can convert Fahrenheit to Celsius and much more.

Comment #237

2009-02-05T11:27:47Z

I am constantly figuring the F to C when spending months each year in a C speaking country!!! For example if a recipe calls for 350*F - I subtract 32 which gives me 318* and then divide by 1.8 which gives me 176.66 or 177*.

As the saying goes "That is close enough for government work"!

Comment #236

2008-02-29T23:52:36Z

Belize does.

Comment #235

2006-04-01T22:42:45Z

That's great to hear; thanks for letting me know it was useful.

Comment #234

2006-04-01T16:13:36Z

Hey, I just moved to Canada from the states and this helped me tremendously!! thank you!

Comment #233

2006-02-04T20:26:20Z

I recently needed to convert between .1 degrees Kelvin and degrees Fahrenheit.

It was fun figuring out the formula to make it work as efficiently and with as little rounding error as possible. I don't usually need to do any math at work.

Comment #232

2006-02-02T20:07:49Z

You're welcome! Have a wonderful time.

Comment #231

2006-02-02T17:24:33Z

Thanks! This was really helpful. I will definitely use this when I am in Australia in a week! Thanks again.