"You rely on percentages," a club player said to me, "I believe in Murphy. If on an actuarial basis something will go wrong 50 percent of the time, it'll actually do so 90 percent."

Numbers don't lie, but they may seem to fib a little if your dummy play is shaky. In today's deal, West led a diamond against 3NT, and East took the ace and led the seven of hearts.

South finessed with the queen, and West won and returned a heart to the ace. South then took the A-K of clubs, expecting four clubs, three spades, a diamond and a heart, but when West discarded, South won only eight tricks.

SURE THING

"You can tell me that the chance of a losing heart finesse plus a 4-1 club break was 14 percent," South grumbled, "but if I'm declarer, it's all but a sure thing."

South had a 100 percent play. He must rise with the ace of hearts and lead the king and a low diamond. West takes the queen, but dummy's jack is good for South's ninth trick, and his queen of hearts is safe from attack.

DAILY QUESTION

You hold: S Q 6 4 H A Q 3 D K 8 6 C K Q 5 2. Your partner opens one heart, you jump to 3NT and he bids four diamonds. What do you say?

ANSWER: Your 3NT response promised a balanced 16 or 17 points; your partner has a two-suited hand and may have slam aspirations. If you held a prime hand such as A 6 4, K 5 4, A J 6, A 8 5 2, you would try for slam, but as it is, your secondary honors in the black suits will probably be wasted. Bid four hearts.