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How to Make Decisions?

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I was stucked on the question: “What do I going todo now? SW:ToR or some music creation?”.

I just couldn’t decide. But I assumed, I had wish to play some SW:ToR PvPs to about 70%, and I would like to drop a 7/3 coin instead of a classic 1/1 coin.

A bit of quick JavaScript helped me through:

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decide = function (x) { return Math.random() * 100 < x; }

This should return true with a probality of x %….

I was quite sure, the random number must be less then x, but did some tests to prove it:

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n=100;l = []; for(i=0;i<n;i++) l[i] = decide(70); s=0; for(i=0;i<n;i++) s+=l[i]; s / n
=> 0.64

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n=1000;l = []; for(i=0;i<n;i++) l[i] = decide(70); s=0; for(i=0;i<n;i++) s+=l[i]; s / n
=> 0.716
n=1000;l = []; for(i=0;i<n;i++) l[i] = decide(70); s=0; for(i=0;i<n;i++) s+=l[i]; s / n
=> 0.685

and the big ones :D

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n=10000;l = []; for(i=0;i<n;i++) l[i] = decide(70); s=0; for(i=0;i<n;i++) s+=l[i]; s / n
=> 0.7039
n=10000;l = []; for(i=0;i<n;i++) l[i] = decide(70); s=0; for(i=0;i<n;i++) s+=l[i]; s / n
=> 0.6986
n=10000;l = []; for(i=0;i<n;i++) l[i] = decide(70); s=0; for(i=0;i<n;i++) s+=l[i]; s / n
=> 0.6971

And for fairness, my very first result of decide(70) is qualified for my final decision. Happily, it was

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decide = function (x) { return Math.random() * 100 < x; }
decide(x)
decide(70)
true

:D

P.S.:

You can sometimes take a look at my twitch channel

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