As per the question it is given, probability of winning a game is $5/11$

We have to find out the probability of losing,

Thus,

P(winning)+P(losing) $=1$

Now,

P(losing)$=1–$ P(winning)

$=1–(5/11)$

$=(11–5)/11$

$=6/11$

Hence, probability of losing a game is $6/11$.