Sunday, January 5, 2020

functions - Is 4.99999......... exactly equal to 5?

I'm a student of 10th std. Recently our teacher asked a Question that


"Is 4.999...equal to 5 or not?" Everyone said that is isn't equal or it is approximately equal. Teacher too agreed to that. But I did't agree. I opposed the teacher as I think it is precisely equal to 5. I also prove but then too she isn't satisfied. Can you please explain what is right and what is wrong in this case?Please Justify.



   Proof that I showed : let x=4.999...  (a)
therefore, 10x = 49.999...
10x -x = 49.999... -4.999...
9x = 45
x = 45%9
X= 5 (b)
hence (a) =(b).
And therefore, ***4.999... = 5***

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