The Student Room Group

further stats question

Im a bit stuck on this question and would really appreciate some help :smile:

Asha, Davinda and Jerry each have a bag containing a large number of counters, some of
which are white and the rest are red.
Each person draws counters from their bag one at a time, notes the colour of the counter
and returns it to their bag.
The probability of Asha getting a red counter on any one draw is 0.07

(b) Find the probability that Asha gets a red counter for the second time on her 9th draw.
If she gets a red counter for the 2nd time on her 9th draw, how many red counters did she get in the first 8 draws? What's the probability of that happening?

She must then get a red counter on the 9th draw. What's the probability of that happening?

So what is the probability of those 2 things happening together?

Quick Reply

Latest