Question

the spinner is spun until one one of the five edges of the pentagon what is the probability that the number it lands on is odd

Answer 1

The spinner has the shape of a regular pentagon, this means that all 5 triangles are equally sized. This also means that each value has the same probability of happening.

So if the possible outcomes are 1, 2, 3, 4 and 5 and they all have the same probability then: P(1)=P(2)=P(3)=P(4)=P(5)=1/5

Of all possible outcomes there are two that are odd numbers: "2, 4"

So for the event " the number the spinner lands on is od" there are two possible outcomes 2 or 4

P(2 or 4)= P(2∪4)= P(2)+P(4)= 1/5 + 1/5= 2/5

The correct option is B.