This is awesome thank you so much. I'm dealing with a pretty crappy Stats professor who essentially makes you teach yourself. Thank God for Khan Academy because without this I would definitely be considering dropping the class.
Had some pretty awful math teachers in my life who never really helped me when I needed it. In college and taking statistics for the 2nd time after failing it once, got behind one day, and thanks to you I'm back on track!
It's funny, I learn more from this channel in like 15 mins, than 60+ PowerPoint slides and a chapter of textbook reading over 3 hours... Thanks for the awesome content!
Thank you for introducing me to the ck12 website , this website is trully another gem just like Khan Academy , growing up i always thought and had this prejudice that it was boring and hard , but you make it easy and fun , i think i fell in love with math i always want to learn more even tho im 28 yo
I'm studying for the DAT and I came across a practice problem similar to this one but worded differently. I'm glad I came here after reading the explanation because they were not clear. This video cleared everything up and now I completely understand how to approach these problems now! Thank you!
Khan, your methods of solving these problems saved me tons of stress and time. I love you and I hope you keep up your great work. P.S. Your interview with Elon Musk was a great watch also!
This is what I have been looking for! Finally a few videos outlining how to complete actual questions. Theory is great to know, but it really wasn't helping me actually answer any of my questions in assessments.
Hi I have a question; 1). Weights of adult women have a mean of 143 poundsd and a standard deviation of 29 pounds. Approximately what percentage of adult women have weights between 114 and 201 pounds? 2). If 350 adult women are randomely selected, approximately how many would have weights between 114 and 201 pounds?
Okay, I understand how you would get this. But I have a problem with the same concept but I cant seem to get it! 1. The pulse rates of healthy adults are normally distributed with mean 72 and standard deviation of 5. a) What percentage of healthy adults have a pule rate over 80? (Hint: You may want to use Excel here.) at the 95% mark it's 82. do I still use the same method? Is there more calculations?
You can not mix kg and grams like that. He kept saying the standard deviation is in grams but the math he works out must make it also in Kg like the mean value.
what if the value lies within a std. dev not exactly as the point mentioned example mean=750,sd=150 and probability greater than 700...... withour using pnorm() or any z-table ...
Hold up... answer B looks incorrect to me. Between 7.3 & 11.7 would not make up 95% because half of 16% is 8%, and on both sides of the 68% there would be 8%, making a total of 16% being added to the 68, making the answer 84%. Please explain how I am wrong
Between two standard deviation falls to exactly 2 standard deviation so you follow the empirical rule . You only subtract and divide when you are calculating less than or above standard deviations
On c), I'm confused and wonder what I'm doing wrong. If 3 standard deviations represent 97.7% and that calculates 100 - 97.7, I'm getting 2.3 which, when divided in half (half for below the 3rd standard deviation and half for above the 3rd standard deviation) splits up into 1.15% each. Why am I not getting the same answer (.15%)? (Scratching head and biting nails!)
You had a misunderstanding, The normal distribution table is considered as 1. He showed that if 1 sd is 0.68 then the rest of the area is equal to 0.32 (1-0.68=0.32). Less than area would be here 0.16 (0.32/2=0.16) and more than 1 sd would be symmetrical, which is also 0.16
Why is it .15% shouldn't it be .13% 12.8-9.5=3 Than you go find 3.0 on the z-table which is .9987 And because it's above 12.8 you subtract by 1 getting .13% how did you get .15%
every time I encounter difficulty I end up at Khan Academy!!! I love your contributions.
+Bat K same here
Same!
I'm passing my test tomorrow! :D! Thank you! What took my professor 2 hours to explain you managed to easily refine in 10 min.
Npc comment
@@joseluisclaro9087 L comment.
ayo bro just realize how many lives you are changing by being a great teacher thank you for helping me with this concept you made this so easy!
I love you!!!! My teacher doesn't explain well at all and I couldn't figure out how to do this for my life in class.
Khan, thank you for helping me pass most of my classes all the way since middle school up until now in college. You are the best instructor ever!
Its been 10 years already, and you're sill helping people thanks a lot I have an exam tom haha god bless!!
like i always tell people, if they are dump in these times, they are indeed dump. thanks much, this was a great help.
by the minute 6:58 it was crystal clear for me. Thank you so much!
This is awesome thank you so much. I'm dealing with a pretty crappy Stats professor who essentially makes you teach yourself. Thank God for Khan Academy because without this I would definitely be considering dropping the class.
This guy has been helping me since 6th grade, I’m a senior in college now
Had some pretty awful math teachers in my life who never really helped me when I needed it. In college and taking statistics for the 2nd time after failing it once, got behind one day, and thanks to you I'm back on track!
Hey Khan Academy guy, your voice is so soothing to me when I'm stressing out doing my statistics homework.
Sal Khan
He's more than a teacher. He's a god.
It's funny, I learn more from this channel in like 15 mins, than 60+ PowerPoint slides and a chapter of textbook reading over 3 hours... Thanks for the awesome content!
hey sorry to bother you but how did they got the 16 percent im so null at it
omg.. thank you so much.. God will bless you for helping me with this difficult math..
well idk what to tell you
Thank you for introducing me to the ck12 website , this website is trully another gem just like Khan Academy , growing up i always thought and had this prejudice that it was boring and hard , but you make it easy and fun , i think i fell in love with math i always want to learn more even tho im 28 yo
whoever this guy is... THANK YOU SO MUCH!! SO MAKE YOURSELF A COOKIE BECAUSE YOUR DETAIL LITERALLY JUST SAVED MY LIFE!!
Just found this page, thank god! I could not understand this Rule and now I do! Whoo Hoo!
I'm studying for the DAT and I came across a practice problem similar to this one but worded differently. I'm glad I came here after reading the explanation because they were not clear. This video cleared everything up and now I completely understand how to approach these problems now! Thank you!
Actually stand a chance on my test tomorrow. Thanks man
Khan, your methods of solving these problems saved me tons of stress and time. I love you and I hope you keep up your great work.
P.S. Your interview with Elon Musk was a great watch also!
This is what I have been looking for! Finally a few videos outlining how to complete actual questions. Theory is great to know, but it really wasn't helping me actually answer any of my questions in assessments.
Beautifully explained. 🙏 Thankyou
thank you for this video. helped me alot
It's good ... I like this method to teach .. it's understandable and simple way to recognise the topic ...
Thank you so much KhanAcademy! I swear to God I was hating this rule until right now!
**Tears** thank you!!
thank you so much for helping me.
Thank you so much, very helpful, and congrats with your son, he must be 7 years old now !
Great video! Simple, clear and efficient ;)
Thank you!!! This emperical Rule thing was KILLING ME! I get it now.... You are a life saver!
What if it asked what the percentage was for it to fall in the range of 7.3kg and 10.6kg? Can you explain how to do it if it asked that range?
thank you so much. im ready for my final tomorrow
Thank god for these tutorials
i love this guy he is so smart !!!
Omg!!!! Life saver 🙏🏽🥂
my teacher is foreign i was going to switch classes but u r def helping me pass this semester LOL
awesome.. u just made it so much simpler
OMG thank you so much ❤
thank you for your efforts. Keeping doing great jobs
Thank you so much. I love how you make sats more enjoyable.
Really helpful! Thank you sir!!!!
Khan for President!!!
VERY HELPFUL
Thank you so much!!!
thank you so much, these videos help allot
o--- = 1.1 kgs right? and not 1.1 gms
Very useful
Awesome job at explaining, thanks
I found this very useful.
Thank you! You are a great instructor!
Excellent to get me started; thank you!
Hi I have a question; 1). Weights of adult women have a mean of 143 poundsd and a standard deviation of 29 pounds. Approximately what percentage of adult women have weights between 114 and 201 pounds? 2). If 350 adult women are randomely selected, approximately how many would have weights between 114 and 201 pounds?
Very Well! Thank You!
9.5 kg and 1.1 grams ????
for a min it was messing me up so bad cuz i always try to solve before vid
This was surprisingly easy. Wow.
This is amazing! Great work!
Omg! Thank you! I finally get it!!
better than my maths teacher
What if you are to find the probability between 11.2 and 9.8
you are the BEST
Well Explained...
Thanks for sharing!
Okay, I understand how you would get this. But I have a problem with the same concept but I cant seem to get it!
1. The pulse rates of healthy adults are normally distributed with mean 72
and standard deviation of 5.
a) What percentage of healthy adults have a pule rate over 80? (Hint:
You may want to use Excel here.)
at the 95% mark it's 82. do I still use the same method? Is there more calculations?
Platos Advocate You only use empirical rule if the SD is a factor of the value you want to calculate for.
Thanks man! thanks for sharing!!
the question is in grams or kilograms?
Shouldn't part A be 34% not 16% since it is asking for everything less than 8.4kg. I think it should include everything on the bell curve below 8.4kg.
thank YOU SO MUCH
Thank you
you rock! best explanation.
MANY THANKS!
Thank you!!!!!!!!!!
You can not mix kg and grams like that. He kept saying the standard deviation is in grams but the math he works out must make it also in Kg like the mean value.
What does the mean mean?
at 06:33 you say that 68 / 2 = 32, well, its 34.
THANK YOU VERY MUCH :-)
Thank YoUUUUUUUuUUUU
Each of the legs of the 68% region are Left=34% & Right=34%, not 32%.
68% is the body without the two legs, and 32% is the remainder. It's not the two halves of the body.
thanks :)
thank you my lord
Wouldn't 1 SD get you .34?
What software do you use for drawing these sketches? I use Libreoffice draw and can't stand it .
greattttt thanks
beautiful
what if the value lies within a std. dev not exactly as the point mentioned example mean=750,sd=150 and probability greater than 700...... withour using pnorm() or any z-table ...
Hold up... answer B looks incorrect to me. Between 7.3 & 11.7 would not make up 95% because half of 16% is 8%, and on both sides of the 68% there would be 8%, making a total of 16% being added to the 68, making the answer 84%. Please explain how I am wrong
Between two standard deviation falls to exactly 2 standard deviation so you follow the empirical rule . You only subtract and divide when you are calculating less than or above standard deviations
i love these c12 problems
Use the steps shown in the video, and figure it out yourself.
On c), I'm confused and wonder what I'm doing wrong. If 3 standard deviations represent 97.7% and that calculates 100 - 97.7, I'm getting 2.3 which, when divided in half (half for below the 3rd standard deviation and half for above the 3rd standard deviation) splits up into 1.15% each. Why am I not getting the same answer (.15%)? (Scratching head and biting nails!)
It’s 99.7 not 97.7
*MORE than one sd below the mean (LESS than one below would be 34%). Very helpful video, just a reminder you are still human.
You had a misunderstanding, The normal distribution table is considered as 1. He showed that if 1 sd is 0.68 then the rest of the area is equal to 0.32 (1-0.68=0.32). Less than area would be here 0.16 (0.32/2=0.16) and more than 1 sd would be symmetrical, which is also 0.16
these are very low level problems i need tough problems to get good grades .
I finally get it
Just wondering why is it .15%
bless you
@HowAboutSomeTruth1 its 1.1 Kgrams
I never knew baby girls were almost weightless...
Sweet. Now I only have to remember 68, 95 and 99.7 =)
Why is it .15% shouldn't it be .13%
12.8-9.5=3
Than you go find 3.0 on the z-table which is
.9987
And because it's above 12.8 you subtract by 1 getting .13% how did you get .15%
my hero
isnt the probability 0.025?