Question

A game of chance consists of spinning an arrow which comes to rest pointing at one of the numbers 1,2,3,4,5,6,7,8 and these are equally likely outcomes. What is the probability that it will point at:

(ii) an odd number.

Answer 1

Sample space, S = {1, 2, 3, 4, 5, 6, 7, 8}
∴ n (S) = 8
Now,
Let B be the event where the arrow points at an odd number.
We have:
B = {1, 3, 5, 7}
$\therefore$ n (B) = 4
And,
P (B) = $\frac{n\left(B\right)}{n\left(S\right)}=\frac{4}{8}=\frac{1}{2}$
$\therefore$ Probability that the arrow will point at an odd number = $\frac{1}{2}$