Basic suitplay problem

[phoenix214]

I have some problems understanding the position, HHT9x opposite Hx(H=A/K/Q), How should the suit be played for the better result, should i play for the drop or for the finesse because checking online tables didnt help, two sources gave different opinions, and doing my math im maybe missing something.

It seems that if im finessing, then im wining if Jxxx is in front, and loosing if Jxx or Jx is behind. Looking at percentages online i get that 4-2 split is 48,5 and a 3-3 split is something around 35%, so it looks like finessing is worse. On the other hand how does the problem change if i remove the 9

Can anyone explain me this position, cause im a bit confused about it

[RGranville]

Playing for the drop is better, by a margin of about 10%.

 

For simplicity, use the approximate percentages of 48% for a 4-2 break and 36% for a 3-3 break.

 

Playing for the drop wins against a 3-3 break (36%) and against Jx in either hand (one third of all 4-2 breaks, i.e. 16%). Total probability is 52%.

 

Taking a second round finesse wins when the jack is onside (50%), provided that the suit breaks 3-3 or 4-2 (84%). Total probability is 42%.

 

You can obtain the same result using your approach of considering winning cases and losing cases.

 

Without the 9, the play for 5 tricks is exactly the same.

 

But if you only need 4 tricks, then taking the second round finesse acts as a safety play. It only gains about 6% of the time, so wouldn't normally be the right play at matchpoints.