I was confused as well,but the solution is something like this.
Let's assume the question is to find the probability of drawing second card as heart instead of 10th?
How we will approach this problem is:
A) find the probability that first drawn Is heart and second drawn is heart too i.e. (13/52*12/51)
B) find the probability that first drawn is not a heart and second drawn is a heart(39/52*13/51)
Adding the two will give you 1/4.
The above example is to give a sense of what is happening in this question.
Since we don't know the outcome we can't assume weather the first draw is a heart or not a heart. We added the outcome of two situations.
I see a lot of people saying how can the probability of drawing 10th card as a heart be 1/4 when all the cards from 1 to 9 can be heart. Yes! Certainly it can be but its one of the cases. Adding all such cases will give you 1/4.
And had we known the result of previous outcomes, indeed the question would be different.
As
Bunuel said. May be laura knows the outcome but we don't.
Great question.
Thanks guys!
Regards
M
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