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Level 2 B19 solution

#1 User is offline   Knurdler 

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Posted 2021-February-14, 12:33

My first post here. If it is in the wrong place, someone please tell me.
I did search for this topic but found nothing.

My question is on the solution to Bridge Master Level 2, Deal B19.

The solution says the only play is to drop Q&J of trump. That is true for the given distribution.
However, if the cards out were to lie 4/1 with a singleton honor, then the standard play for this combination (K, then low to 10) would succeed and playing K,A would fail. I estimate (not proper math) the probability of the given distribution is about 6.8% and the probability of 4/1 with singleton honor is about 11%. I would love a second opinion on this. Question 2: after leading the K and dropping the J, should one apply the principle of restricted choice and assume a 4/1 split?
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#2 User is online   smerriman 

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Posted 2021-February-14, 13:09

The solution outlines why playing for a 4-1 trump split with a singleton honor does not succeed. You will lose the 4th round of trumps even after you take a successful finesse on the second round.

The only way you can ever take four trump tricks is when QJ is doubleton.
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#3 User is offline   shyams 

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Posted 2021-February-14, 13:18

If you notice the small cards held by opponents in, if they split 4-1 you will definitely lose one more heart trick. Having already lost a diamond trick with the opening lead, you cannot afford to play any layout where you are saving yourself an extra one undertrick.

You are correct that the odds favour a finesse as per restricted choice. However, after your restricted choice finesse has won, you will still have the following card layout in trumps,

..Dummy
94

.........East
........Q8

Declarer
A3

... and you will find you cannot repeat a finesse to avoid a loser.
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#4 User is offline   LBengtsson 

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Posted 2021-February-14, 13:25

View Postsmerriman, on 2021-February-14, 13:09, said:

The solution outlines why playing for a 4-1 trump split with a singleton honor does not succeed. You will lose the 4th round of trumps even after you take a successful finesse on the second round.

The only way you can ever take four trump tricks is when QJ is doubleton.


Yes. The small cards 876 emphasize how important they are. If either East/West have Q876 or J876 then contract can not be made. Change the opps to QJ875 then you can might make the contract if 4-1 and Q or J drop singleton on first round of trump with good guess and 6 in right hand. Probability less than dropping QJ as doubleton, so solution of problem on Bridge Master is right.
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