Carpenter Trick: How To Subtract Fractional Numbers Quick & Easy

[@ordinaryguy6869]

That is awesome! I wish I would have had you for my teacher many years ago when I started woodworking. Thanks Herrick.

[@steveegbert7429]

I just watched your addition video and this goes right along with it as a super simple solution to us without the strong math DNA.

[@Kinjo2008]

*Comment for the algo. I watch all your videos and appreciate these helpful golden nuggets you share. Thank you.*

[@desparky]

Very easy to do in your head. 440-124=316mm. In Australia we converted to metric in 1971 when I was a kid. I can use metric and imperial, but metric is so much simpler and faster to work accurately. Also the conversion between length/area/volume naturally make sense.

[@boudhanotdead8855]

Love down to earth tips!

[@ronnym1977]

Incredible and so user friendly! Thank You Sir, and God bless your teacher.

[@lourias]

My daughter is "mathematically challenged." I do not know why she did not inherit my calculus-based awesomeness. My grandsons love math! Maybe math wizardry skips generations.

[@georgeriverasr.6298]

Just FREAK'N awesome Bob😊😊😊😊😮😮😮!!!

[@alexduenas6991]

Thank you

[@jimbola77]

I love math so much! but I'm just a dummy at it! that is awesome sir! thank you for sharing....

[@rickthorley4378]

America might consider joining the first world and go metric instead of relying on Bob to come to work with you.😂

[@cynthiafisher9907]

I can do it pretty quickly in my head, but this is a cool trick as well.

[@James3-8]

How? The part that gets me is having to borrow from the 17 to be able to subtract from 14/16, pretty hard to do in your head.

[@cynthiafisher9907]

Just take one from the 17 and add 16 to the 5. You get 16 21/16. Then change the 7/8 to 14/16. 21-14 is 7, so you get 12 7/16.

[@stevecooper6473]

Round up 4 7-8 to 5 even, subtract that from 17 7-16, and add 2-16 (i.e. 1-8). Easy.

[@DawnBarb]

Hey hey from iowaaaaay! Whaaaa? Hooow? WAHOOOOOO THANK YOU! That’s fantastic!

[@keithcronk7980]

Wow thAnk you & bob have a great day

[@lark_ch1]

Other way is to fold your tape side to side and just read the answer... then no pencil and no surface needed. its same as slide rule and works for both add/sub

[@richardM980]

so help me out here. 17 5/16 minus 4 7/8 or ( 14/16) would seem to be 12 9/16 . That is 5 minus 14 = 9 rather than 7. Am I missing something?

[@MiloOnYT]

This is what i said 😂 im like what??

[@job38four10]

Ok thats good, if 25 years ago, but how much time does it take to find a flat smooth long enough board to do all this constant math, not to mention pencil with eraser, and what if it was 17'-5/16" - 4'-7/8", not to mention thumbling around with a flip-floppy tape............. Today who doesn't have smart phone on them all the time, with a smart phone fraction app, one can do all the math that is needed to build anything anywhere, no need to carry flat board in pocket or pencil with eraser, also I find it hard to make phone call on a board no matter how smooth the board is...... PS you did make a good video, short and to the point..........

[@geoffbembridge868]

Absolutely brilliant, once again. Great Herrick.

[@SC-bg8wf]

Just switch to mm like the rest of the world, So much simpler and less prone to errors.

[@radishpea6615]

Just wondering if people will learn maths and fractions from this method.

[@philliphoward7455]

I just convert fractions to decimals then add, subtract or whatever I have to do. My answer of course is a decimal that I convert back to a fraction.

[@JIMMYBUSHIDO]

I've used my system which can be used either imperial, or metric. Fir instance if I want 8 and a half plus 1/32.... I'd say to myself... " Big 8 and a half. "

[@DavidRavenMoon]

I can’t do math in my head, but it’s good to remember that 7/8 = 14/16. Makes it easier to add or subtract 5/16. But this method is better.

[@jasonnester9514]

Damn that’s awesomeeeeeee

[@ronaldclobes9340]

Shucks, that's a little simpler than how I would have done it!

[@Kris-82]

genius

[@user-ic2ug8ys1z]

Wow. 😃🌱🐢

[@Hipyon]

I think you misunderstand the imperial measuring system The answer comes in my head before you pick the pencil up 7/8=14/16

[@dallasarnold8615]

Barefoot, you seem to misunderstand, there are more numbers involved. Now subtract 4-14/16 from 17- 5/16.

[@Hipyon]

@@dallasarnold8615 The same as any other subtraction 5-14 you can’t do it so you borrow 1 which is16/16 Then subtract 21-14 =7/16 then 16-4 =12 12”7/16 😊 But actually when I did it in my headI rounded up 4 14/16 to 5 subtracted five and then added the 2/16 I had rounded up

[@nando9273]

That would only work for numbers under under 25 ft

[@aldob5681]

fractional number are a/b. your numbers are simply non integer number

[@aethom10]

Sir 😮

[@stevenlengyel9701]

Common denominator

[@stevecooper6473]

Sorry that should have read 17 5-16.

[@deserado11]

... metric ...

[@TomKaren94]

It's sad that this video has to be made.