Temperature conversions, Centigrade to Fahrenheit and visa versa

[GatsbysCruiser]

More and more thermometers are coming out in Centigrade rather than Fahrenheit which I was raised with.
Equipment temp gages are using centigrade, supposedly more accurate,

I may have come up with an easier solution.



Here is what I came up with.

If the CENT temp is 20, the Fahr temp is 68

The formula is F = 20C times 9/5 + 32



My method

Take 20C, divide in half, then divide in half again and add 32
so

20 plus 10 plus 5 plus 32 equals 67

in the case of a odd answer, round UP

My method ----→ 21C plus 11 plus 6 plus 32 equals 70F

the forumula ---→ 21 times 9/5 plus 32 equals 69F



Reversely

Fahr to Cent is


my method---→ 70F minus ¼, minus 32

------------------→ 70F divide by 4 and subtract that answer, minus 32

so ---------------→ 70F minus 17, minus 32 equals 21C

in this case you would not round up


the formula----→ 70C minus 32 times 5/9 equals 21.111

simpler way to get the answer, esp in the field


Let me know if there is a problem to this solution, I will remove this if it is wrong.
Thanks Ya' all.

 

[Ken B]

Yes, that is what I learned in middle school over 60 years ago. (9/5 +32)
I never have much trouble translating it but I can not relate to the C. number without converting it to F. first. If someone tells me it is 25 C. I can not relate to whether that is hot or cold. I seldom need to do this and when I do I only need to be close. I do next to nothing in C. When I see something like 250 C. I have no idea what that is and I am forced to convert it. My immediate guess is 250 C. would be something around 500 F.

I had dinner one time with a Canadian trucker here in Induana. He was unhappy with the converstion of miles to km. He said that the cops use to give you about 6 mph lea way. Now they still give you the same 6 but it is in km which is only around 65% of the previous amount.

 

[GatsbysCruiser]

KM is easy, like KMH, divide that number by 8 and multipy by 5 for MPH

Some of the thermometers I purchased were in C and not able to change to F. So I had to come up with an answer to use them. I tried charts but always lost them.
When I was till working for the company, the equipment had temperature guages in C, nothing in F. We had to use a chart. I'm generally good with numbers and formulas but get tired of having to convert all the time. I had not found this quick method then, guess it didn't bother me enough.
I sat down looking for some easy conversion and saw that this worked well, within a degree or two both from C to F and F to C. I don't know why no one has figured this out before, maybe they have and I am late to the table.
But now I can look at a C temperature and figure it out quickly.

 

[Matt Colie]

Wow,
I'm much too lazy to go to all of that work for temperature.
What ever the reported temperature is, I just add 40.
Then, I need to decide if I need a bigger result or a smaller, so I kind of have to pay attention here to what I started with, but not a lot. Because what I to decide is if I am multiplying or dividing by 1.8 .
When I have done that, subtract that 40 that I started with. Ta-Da.
This works because -40 is where the two are the same.

Matt - yes, I'm and engineer

 

[RF_Burns]

For temperature, instead of converting back to F, it may be easier to think in C and recognize a few temperature levels. You already know that 20C is low room temp 25 is warm room temp and 30 is getting hot. 10 to 15 is jacket weather and 0 is freezing point so wear a coat.