Multiplying and dividing with significant figures | Decimals | Pre-Algebra | Khan Academy

Multiplying and dividing with significant figures

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[fransheskarivera]

Have been going over this in chemistry and could not understand it, explained by 3 different professors and all it took me was 9 minutes to learn. Wow. Thank you!

[하루-rz]

Why do we even need to attend school if we can just watch these 8minutes of clips regularly to learn -0- school just wastes time esp with bad teachers.. I'd do better off with myself with these videos

[yneii]

Hey, I just wanna thank you so much. Because of quarantine and this normal, we now have online classes and I'm a very slow learner but thanks to you I learned a lot, and I was able to catch up. You teach better than my teacher. Again, thank you!!!!

[abaaderaw]

I am a high school fresh man but Iam still to be 13 year old high school chemstry is quite hard comperd to junior but your vidos helpd me alot

[Wolfeywolf]

I left class kind of confused, so this video really helped. Thank you so much :)

[Doomman]

I’ve got a chemistry retake test in a few hours and this video helped me a lot, thank you man

[MaceyRosalie]

My teacher didn't even bother teaching this material, just left us to the inevitable inaccuracy of independent learning and assigned everything over the summer -.- 
There's me thinking Chemistry will be the bane of my existence and significant figures are just the beginning when I stumbled upon this video :) Thank you SO much! You are keeping me from failing a torturous semester which will not even be as torturous thanks to your videos :D

[sagewt]

10.1 has 3 sig figs not 2 but thanks for the help

[evan]

It seems a lot of people don't know that this guys has his own website with courses on them. My friend did the calculus course over the summer so that he could take AP calculus his sophomore year of high school.

[EthanIslandGamer]

Thank you soooo much! I would have failed my Physics test if this wasn't here. It made no sense before but now it makes perfect sense. Keep up the good work!

[MakeJerold]

Anybody else here because they have a chemistry test tomorrow? Haha
You are a life saver, Mr. Khanacademy!

[GazaAlley]

cant wait for the next video thanks man!!!

[happyeverafter]

In the final answer, he rounded up (113.931775701 to 114), do you always have to round up?

[jacobstorey]

But what if your final answers has more than 3 significant figures before than decimal and the least amount of significant figures in the equation is 3?

[paulceltics]

thanks; you dont know how important this is for chemistry

[EarthStories_By_JaySolanki]

Hello sir i have a question
Why do we even round off number when its purpose is to give an approximate number by rounding off it ?
We can leave number upto the precision that we were able to measure it. Isn't this is good to do.
Why even i am asking this question is because most time there is huge difference between rounded and unrounded answer upto its precision.

[hello-nqze]

I believe he does know how important it is for chemistry :P, he teaches that also.

[dep]

Do not round until you are done with your calculations. If I only had watched this before college, it would have gave me a decent amount of points

[Bushnurse]

@mathforphysics, thanks, I'll try it

[NoRefundsXD]

Don't you need a decimal after 114 (like 114.) because isn't it ambiguous? Someone clarify please?