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# Conditional probability question

#### gaurav_ry

##### New Member
Football Team A chances are winning is 50%, probability than star player scores a goal when Team A wins the match is 36%.
Star Player scores a goal in 20% of all the matches.

Q1 What is the Joint probability of Team A winning and star player not scoring
Q2 What is the conditional probability of Star Player scoring and Team A losing the match

Please advise.

#### David Harper CFA FRM

##### David Harper CFA FRM
Staff member
Subscriber
here is implied matrix (only doing this b/c it's interesting) Q1: 32.0% b/c conditional Prob(star player NOT scoring | team A wins) = 1 - 36.0% = 64%, such that joint(NOT scoring, win) = Prob(win)*Prob(not score|win) = 50%*64% = 32.0%
Q2: it does not make sense, do you mean "What is the conditional probability of Star Player scoring when Team A loses the match?" If so, 4.0% = 2%/50%

#### gaurav_ry

##### New Member
Thanks David, well understood.

I tried it to put it in multiplication formula format, assume it to be correct as well

Q1: 32.0% b/c conditional Prob(star player NOT scoring | team A wins) = 1 - 36.0% = 64%, such that joint(NOT scoring, win) = Prob(win)*Prob(not score|win) = 50%*64% = 32.0%

joint(scoring, loosing) = Prob(loose)*Prob(score|loosing)
so
Prob(score|loosing) = joint(scoring, loosing) / Prob(loose)
= ( prob(loosing) * prob(score|loose) ) / Prob(loose)
= 0.5 * 0.04 / 0.5
= 0.04

#### Flashback

##### Active Member
Quants chapter is divided to Probability Distribution, regression and volatility clustering models sub-sessions. What are odds that Probabilities have more than 7 Qs in total of 20 Quants questions?
The last two are pretty straightforward but have some problems with the first group concept understandings.

#### Nicole Seaman

##### Director of FRM Operations
Staff member
Subscriber
Quants chapter is divided to Probability Distribution, regression and volatility clustering models sub-sessions. What are odds that Probabilities have more than 7 Qs in total of 20 Quants questions?
The last two are pretty straightforward but have some problems with the first group concept understandings.
Hello @Flashback

Our exam feedback threads may provide some insight on this, as many members list the questions (or at least the concepts) that were asked on the exams. You can find the most recent feedback threads here:
Nicole

#### Flashback

##### Active Member
Dear Nicole

Thanks. It was partially a joke. In P1 yet I'm struggling with PD and in P2 with entire Credit and Market Risk but gaming an exam is not an option. 