Using the spinner below,
what is the probability
of landing on an odd?
To find the probability
of an event, we compare
the favorable number of outcomes
to the total number of outcomes.
So, for the probability
of spinning an odd,
let's first determine the
total number of outcomes.
Looking at our spinner,
notice how it's divided
into eight equal-sized
sections, each section numbered
from one through eight,
and therefore there are
eight total possible outcomes.
And now consider the
favorable number of outcomes,
which would be the
sections with odd numbers,
and therefore, one is
favorable, because one is odd.
Three is favorable, because three is odd.
Five is odd, so five is
favorable, and so is seven.
Seven is odd, so seven is favorable.
These are the favorable outcomes.
Notice how there are one, two, three, four
favorable outcomes, which
means their probability
of spinning an odd is four-eighths,
but this does simplify.
There's a common factor of four.
Four-eighths simplifies to one-half.
So the probability of
spinning an odd is one-half,
but probability is often
expressed as a decimal
and a percentage, so let's also show that.
We should recognize that
one-half is equivalent to 0.5,
or five-tenths.
If we didn't recognize this,
of course, we could divide.
One divided by two equals .5.
To convert to a percentage,
we would multiply by 100,
and add a percent sign,
or move the decimal point
to the right two places,
and add a percent sign,
which would give us 50%.
So if the probability of
spinning an odd is one-half,
this means theoretically, we
expect to roll an odd number
one time out of every two spins.
Having a probability of 50%
means, we expect to land
on odd 50% of the time, or
50 times out of 100 spins.
I hope you found this helpful.
