Probability of Event 'Not Occuring' Video Lecture | Mathematics for GRE Paper II

welcome to electron line and now we're
going to talk about another part in
probability and that's called the
probability of an event not occurring
now the concept is fairly simple the way
you typically want to attack this is
simply saying that the probability of an
event not occurring and that's why we
write like this not a let's say that the
event is a and we're tossing a die and
the event a is equal to four the sample
space of course is one through six and
so the probability of Abel occur would
be just one possibility out of six or
one out of six but what is the
probability that a will not occur the
best way to write it is 1 minus the
probability that a will occur so in this
case the example that would be 1 minus
what is the probability that a will
occur welder's one outcome out of a
total of six possible outcomes so that's
minus one over six which is equal to
five over six and that would be the
probability that a will not occur so the
concept is very simple and
straightforward of course there's some
more complicated ways in which we have
to look at this but at least this
concept that's how you want to attack it
always take one minus the probability
that the event will occur and that gives
you the probability that the event will
not occur and that's how we do that the
fastest one in a while huh