Given that probability of winning a game P(E) $=0.3$
We have To Find that Probability of losing the game
As We know that the sum of probability of occurrence of an event and probability of non-occurrence of an event is $1$.
Therefore,
$P(\overset{\scriptscriptstyle\rightharpoonup}{E})=0.7$
$P(\overset{\scriptscriptstyle\rightharpoonup}{E})=0.4$
$P(\overset{\scriptscriptstyle\rightharpoonup}{E})+P(E)=1$
$0.3+P(\overset{\scriptscriptstyle\rightharpoonup}{E})=1$
$P(\overset{\scriptscriptstyle\rightharpoonup}{E})=1-0.3$
$P(\overset{\scriptscriptstyle\rightharpoonup}{E})=0.7$
Hence, the probability of losing the game is