The panzer has spoken

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WTF why did no one mention this to me when I was struggling with math as a kid?
- They probably did, just not explicitly:
  You could write (61/100)50 = 6(501/100)
  It only uses the commutative property of multiplication and the fact that % is another way of writing 1/100.
  Maybe also worth remembering that "x% of y" is just x/100*y
  
  I'm confused again.
  
  The word percent is exactly that per cent, which basically means parts of hundred. E.g. 10% are 10 of 100, or 60% are 60 of 100. You can also write this mathematically as 60/100 or 60÷100, which is 0.6.
  Now in general: x% are x parts of 100 or x/100 or x÷100. If you want to calculate x% of y you just multiply it: y × x% = y × x ÷ 100.
  
  This is one of those "maths is magical" moments, I guess.
  
  Mathemagics.
  
  By what part?
  
  I totally remember being taught this. It's just way easier to break down percentages in terms of the nearest 1% or 10% times the number in the percent times the number you're taking the percentage of. You don't have to do the math for the 1 or 10 percentage as long as you remember that a 10% means move the decimal left once and 1% means move the decimal left twice. The rest is just basic multiplication.
  40% of 59 = 10% of 59 times 4.
  So...
  4x59=236
  or
  (4x50=200) + (4x9=36)= 236
  10% means move the decimal left once,
  Therefore 40% of 59 is 23.6
  With that you can easily do more complex percentages mentally like...
  62% of 35 = 10% of 35 times 6 plus 1% of 35 times 2.
  35x6=180+30=210 at 10% so 21
  plus
  35x2=60+10=70 at 1% so 0.7
  Therefore 62% of 35 = 21.7
  
  While I get your sentiment, I'm always baffled how people fail to just memorize some basic formulas/equations and then just to plug and play:
  1÷kⁿ = k⁻ⁿ
  % = 1÷100 = 10⁻²
  k×10ⁿ equals k with its floating point shifted by n to the right for positive n, or to the left for negative n
  That's really all one needs to know for the "problem" at hand. For your concrete example of "40% of 59" that would just be
  59×40×10⁻²
  Just solve that whatever way is easiest. I don't get why people get panic-stricken when they see the % sign.
- Seriously, why didn't anyone?! Would have made my life much easier.
  
  they absolutely taught you the commutative property and transitive property
  
  Yeah but they clearly taught it poorly
- Easy way to do %
  Say you want 6% of 45
  Seems hard right?
  1% of 45 is .45
  .45 × 6 =
  .4 × 6 = 2.4
  .05 × 6 = .3
  2.4 + .3 = 2.7
  So 6% of 45 is 2.7
  Extra:
  Say you want an item that is 40 dollars and it is 20% off.
  10% is 4 dollars.
  20% is 8 dollars.
  So item would be 32 dollars.
  
  that's a shitload of lines of math to write out/work in your head. I learned percentages of x as: 6 * 45 / 100 = x (2.7) If you picture both as fractions, you multiply the opposite and then divide by the other number to get the missing one (x). Hopefully Lemmy renders this well...
  
  6 x
  100 45
  The way I learned it was multiply diagonally and then divide by whatever is opposite diagonally to x.


6	x
100	45

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