Given, in the spinner 8 equal sectors, numbered 1 to 8.
So total numbers = 8.
Let, the probability of spinning a 3 is P(Three) and spinning an 8 is P(Eight).
Now we know that, probability of an event E is
P(E) = (number of outcomes in the event)/ (total number of possible outcomes).
So here number of outcomes for spinning a 3 is 1 and we have got total outcomes = 8.
So P(Three) =
Similarly, P(Eight) =
Probability of spinning a 3 or an 8 = P(Three) + P(Eight)
=
As the denominator is same we can add the numerator.
=
=
Now we have to simplify the fraction by dividing the numerator and denominator by a common factor of them.
The common factor of 2 and 8 is 2. So by dividing them we will get,
=
We have got the required answer.
The probability of spinning a 3 or an 8 is