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A mathematical equation is bothering me. I can't figure out the logic behind it.
"if you had been to two sites that had a 2-1 ratio of men to women, the probability of you being female would be: 1 / (1 + 2 * 2) = 1/5 = 20%"
Why 20%? Why 1 / (1 + 2 * 2) ?
I used to be good at math. Supposedly.
.
It was thundering a bit before, the sky was darkening, and it was getting windy. But then it seemed to pass, without climaxing... without rain. I was going to write that. But a while later, it did start to rain.
.
I just can't stop thinking about it. It's been bugging me since yesterday.
So the probably of you being male would be (1 - the prob of you being female) which would be
((1 + 2*2) - 1) / (1 + 2*2)
which is 2*2 / 1 + 2*2
But Why?
Why multiply those numbers together, and why add one?
"if you had been to two sites that had a 2-1 ratio of men to women, the probability of you being female would be: 1 / (1 + 2 * 2) = 1/5 = 20%"
Why 20%? Why 1 / (1 + 2 * 2) ?
I used to be good at math. Supposedly.
.
It was thundering a bit before, the sky was darkening, and it was getting windy. But then it seemed to pass, without climaxing... without rain. I was going to write that. But a while later, it did start to rain.
.
I just can't stop thinking about it. It's been bugging me since yesterday.
So the probably of you being male would be (1 - the prob of you being female) which would be
((1 + 2*2) - 1) / (1 + 2*2)
which is 2*2 / 1 + 2*2
But Why?
Why multiply those numbers together, and why add one?