There are three ways in which these cards may be held:
+------------------+-----------------+
| _In One Hand._ | _In the Other._ |
+------------------+-----------------+
| K J 10 | x x x |
| K J x | 10 x x |
| K x x | J 10 x |
+------------------+-----------------+
In each of these cases the play is practically the same; lead the
highest card from the weak hand and finesse. If by the finesse you
succeed in forcing the ace, wait until the suit can be led through
the queen.
If you hold this combination with nine or more cards of the suit, it
is often difficult to determine whether a finesse should or should
not be taken; if you play the king and it wins the first trick, you
may drop both ace and queen on the next lead.