Question

How to calculate a probability

Answer 1

Probability is calculated by comparing the odds to a certain event occurring to the number of possible events.

P=$\frac{possibility-of-an-event-occuring}{number-of-total-outcomes}$

For example, take a six-sided dice number 1-6 on each side. The probability of rolling a 4 would be1 in 6 or 1/6. This is because of the six possible outcomes, rolling a 4 is only one of them.

P(4)=1/6

Now take the same dice. The probability of rolling an even number is 3/6. To see why, lets look at the total possible outcomes:

1
2
3
4
5
6

Of the 6 possibilities, 3 are even numbers.

P(even)=3/6 or 1/2