The thing is that the percentage points don’t fully match up. if adding ten percentage points adds 8 Evilar, then doubling it should add 16. However, that doesn’t add up to 140, it adds to 124. 20 percent of 140 is 28, and if you subtract that it would logically go to 112. Vyse, do the percentage points stack, or are the two increases separate?
Correct. From the first increase we know that the price without VAT is 80 Evilar. Having the price for both without and with VAT, we can then calculate the VAT itself after both increases, which is 75% since 140/80=1.75. Therefore, the VAT before doubling was 37.5%, and before adding 10 percentage points it was 27.5%. Now we can calculate the price of a christmas light, which is 80*1.275=102.
@FlareNetworkC The second raising of the tax was doubling the entire thing, not just by the amount it was increased before.
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Ah, I see. I am powerless in the face of the NepNep.
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I sorta didn’t bother to calculate actual % btw.
Just like…
8x10 = 80
140-80 = 60
60/2 = 30
30-8 = 22
80+22 = 102
Ah, you went with the value that the VAT increased the price by at each state.
I kinda want to ask you guys one of those maths riddles just to mess with you a little…
You have two numbers, which multiplied together equals 579 201 525.
The average of these two numbers is 24 837.
What are these two numbers?
This may be either very easy or really unfair btw. I’m actually more interested in seeing how @akafa123 would solve this, sorta to see which of the two methods is more efficient (assuming it’s another one…).
This does not require any form of binary search. A basic calculator and a piece of paper should do
I simply used high numbers to prevent anyone from solving it by trying out all the possibilities, so using a program that would do so is not the right way.
By average, you mean the mean of the two numbers, correct?
Yes.
Actually I’ll add something else in the post.
It’s very frustrating that googling 579201525 comes up with no search results, no matter how I google it.
Ughhhh this is why only having learned up through Algebra 1 is frustrating. I probably could solve it if I’d have gone through Algebra 2 and Calculus yet. The drawbacks of only being a sophomore.
x+y= the average of two number*2
you can do it the long way here
xy=579201525
x=579201525/y
((579201525/y)+y)/2=24837
(579201525/y)+y=49674
(579201525/y)+y-49674=0
579201525+y^2-49674y=0
y1=30975
y2=18699
x1=579201525/30975=18699
x2=579201525/18699 =30975
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I got it too, once I realized that the last digit of x+y had to be a 4. It took me a while to find a list of factors, but once I did, I searched for all the factor pairs that had an average that ended in four. It was a small list though, so from there it went quick.
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Well interesting, just going to show the formula I use (that I basically made myself).
24837^2 - 579201525 = X
A = 24837+√X
B = 24837-√X
Kinda wanted to see the typical way to solve this.
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Was just about to post Usagi’s solution, but alas, I was too late.
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This is the way I solved one of these when I was given it (I think?)
I mean I don’t know maths much at all/never really studied it, but I made my own tricks for some stuff, so I was just interested in seeing what would be “taught” in contrast to what I use.
Glad to see I’m not the only one who’d do it that way.
I think what you posted was much typical than what akafa posted. I mean I’d do it your way 
I’m sure I’ve learned that at some point, but my brain is still in Summer mode. Bah.
I get ya, my brain is in “never gonna use these again coz medicine” mode. And I even learned integrals and such. Ugh. ;_;
If Vyse doesn’t mind, I could share a brief silly little thing from something that Usagi’s puzzle somehow reminded me of even though there is no direct connection. This should be over quickly.
That’s a quarter circle of radius 1. Find the length of the red line.