Probability of z given mean and standard deviation

For similar practice problems, visit the above link.

[rileynelson]

This is all I’ve needed.... the entire


I hate my stat professor.

[benjamindraxler]

Thank you very much for this video. I struggled a lot with those examples because our teacher never used any examples to explain how everything works and this video helped me to understand how everything works.

[ranasingh]

You're such a nice teacher, needless to say . It helped me a lot.

[md.nayeemrahman]

Thanks to you of all
With due respect i ask you that how do you find z= -1.67 from .0475?

[josephinewu]

If 3 things are selected, how would i find the probability that all 3 things exceed a certain value?

[AmarAmreshKumar]

A certain class of students is assessed for mathematical aptitude. The
class average is 70% with a standard deviation of 5%. What is the
probability of a student scoring 80%? What is the probability of a student
scoring 60%? What is the probability of a student scoring between 70%
and 85%? What is the probability of a student not scoring above 60%?

[felistusmutinda]

Example two i have got a different value. First my table only reads up to 0.5 so i have to split the area, 0.5 plus the the other area. i dont know where i am missing out coz i have repeated twice and still got 0.5517.

[morgandaugherty]

This was so helpful! How would you calculate a probability of an (x greater than or equal to or less than or equal to a value)

[tranty]

for number 2, why did you take 1 minus .0918? Is there any rules right here?

[ashleyl]

And what if I'm not sitting in front of a binomial table. How do I work it out without one?

[sirrus]

Thank you Andy!!
I request a clarification though...
Q3, while calculating Z2 we got 0.83
However in Q2 we subtracted Z from 1 because we're calculating greater than
Then why not in this case?

[priteshbarkale]

how to find mean when standard deviation and probability is given??n excel

[remsimath]

Good job boss. Please, is there anything we could do together

[Mary_]

what if we can't use the z-table and we have to find the probability

[hrjyotathwal]

wow i just learned what a z table is 2 days before my exam lol why coudnt my prof just do this

[mercyj]

Question number 3, since there’s a between there. Which means less than and greater than, do we subtract the final answer from 1? Or keep it as it is? Thanks!

[Compuscience-Python-Prog-Exps]

I never sat and watched the video, but I sure do love this guy's website link. I was just checking it all out. It's a great interactive refresher, Hands-on Math Course. Free. Thanks from all of us. Joe👌

[dianlopez]

I dont really know how to solve this..I hope someone can help me answer these problems😊
Mean is 72 with standard deviation of 12, find
A. Proportion above 90
B. Proportion below 90
C. Proportion between 48 and 95
D. Proportion between 75 and 85
E. Proportion above 55
Thank you in advance❤️😊

[acatwo]

OMG, our proff just give us an Christmas activity and she nerver thought this. Thank you so much ❤️❤️

[Tech-Learning]

I went throught this in my data science course and your explanation makes it more clear. I have a question: Why most of your videos are having green background ?