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MadBob@feddit.nl ⁨2⁩ ⁨months⁩ ago

I think you’re overthinking it. The first thing you’re told when you learn algebra is that a letter represents a number and you can say “let a equal (number), b equal (number)…” so you can let pi equal whatever you want for the purposes of one simple problem.

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rooster_butt@lemm.ee ⁨2⁩ ⁨months⁩ ago
But the question is saying to find the volume of a cylinder. Which its clearly wrong.

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- maynarkh@feddit.nl ⁨2⁩ ⁨months⁩ ago
  Well, if we want to be pedantic, they never said that h is the height and r is the radius of the base circle. They could be just random numbers.
  
  Also, since we never calculate with all the digits of pi, it is not any less weird to round to the nearest 5 and say that it’s 5, than to the nearest 0.01 and saying it’s 3.14. It just has a higher amount of rounding error.
  
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  - GiveMemes@jlai.lu ⁨2⁩ ⁨months⁩ ago
    Why are we upset by rounding to the nearest 5 for elementary schoolers when we round to 10 m/s/s for gravity in collegiate physics classes anyway?
    
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    maynarkh@feddit.nl ⁨2⁩ ⁨months⁩ ago
    It’s not even a bad thing to do for quick mental calculations, if you know that you will overshoot. Multiplying by 5 is easy.
    
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CaptSneeze@lemmy.world ⁨2⁩ ⁨months⁩ ago
You’re talking about variables. But, pi isn’t a variable, it is a constant number. This would be more akin to saying “let 7 = 9”.

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- MadBob@feddit.nl ⁨2⁩ ⁨months⁩ ago
  Well I suppose for example rounding to the nearest integer is a method of implying “let 1.8 = 2”, no? Not too outlandish, I don’t think.
  
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gimpchrist@lemmy.world ⁨2⁩ ⁨months⁩ ago
Or as I like to call pi…the little symbol thingy. But exactly yes, you get it.

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- skulblaka@startrek.website ⁨2⁩ ⁨months⁩ ago
  Except pi isn’t a variable. It is a known value that we refer to as pi for convenience, and pi is a fundamental aspect of how a circle is. Saying “let pi equal 5” is all fine and well but is physically impossible, you will not be determining the volume of a cylinder if you let pi equal 5, because the ratio of a circle does not equal 5, it equals 3.14
  
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  - MadBob@feddit.nl ⁨2⁩ ⁨months⁩ ago
    But I suppose part of solving a maths problem is staying within the confines of the question and listening to instructions, so if someone says “using pi equals 5”, I’d just use pi equals five and take my point with grace.
    
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  - gimpchrist@lemmy.world ⁨2⁩ ⁨months⁩ ago
    Okay but they didn’t say 3.14 they made a little symbol thingy
    
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