please in the conditional probability video, we took the probability of the first head of HH …P(HH|1st is H) is 1/2 while the probability of 10 in a dice where the first throw is six i.e…p(AnB) = P(A) * P(B|A) was solved as 1/6 * 1/6…please what’s the difference between the two conditions and why did they have diff approaches

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Hello @Anwana_Ating_uye,

The first one asks for P(HH | 1st is H) which is a conditional probability. At 0:59, the lecture asks this question

What is the probability that both coins land on heads if you know that the first one landed in heads?

Note that the event that the first one is H * has happened*.

The second one asks for P( 1st is 6 ∩ sum=10) which is a joint probability of the two specified events. At 4:03, the lecture asks this question

What is the probability if I roll two dice that the first one lands on six and that the sum is 10

Note that both events * have NOT happened*.

Since the second one is not a conditional probability, they have different approaches.

Cheers,

Raymond