Calculating the probability of an event is very simple if we know the number of favorable outcomes and the number of possible outcomes of the event.

**Number of favorable results**The number of times the event can occur. For example, on a six-sided die we have three favorable outcomes of getting an even number.**Number of possible outcomes**Here we write the number of possible outcomes that the event has. Continuing with the example of the die, we have a total of six possible outcomes.

Once we have the above data, we enter them in the **probability calculator**If we press the calculate button, we will automatically obtain the probability that this event may come true.

## How to calculate the probability of an event

Calculating the probability of something happening is very simple. We simply have to apply the following division:

probability % = favorable events / total results x 100

In other words, the steps to follow are:

**Determine the number of favorable results**we can get in an event. For example, if we want to roll an odd number on a six-sided die, the number of favorable events we can have is 3 (the numbers 1, 3 and 5).**See the number of possible results**for that event. Following the above example of the die, there will be a total of 6 possible events.

With the above data, we simply have to substitute in the formula that we have put a few lines above and solve the operation.

## Examples of probability of occurrence

For example, do you**what is the probability of winning the lottery?**? In this case, we have a total of 100,000 results ranging from the number 00000 to 99,999 but only one of them will make us millionaires. Therefore:

probability = 1 / 100.000 x 100 = 0,001 %

We have **one in 100,000 chance of winning the lottery**.

What about **chances of winning the euromillions**? In this case, we have to match 5 numbers and 2 stars, which gives a single winning result among 116,531,800 possible combinations.

probability = 1 / 116,531,800 x 100 = 0.000000858134861%

The result is devastating because **our chances of winning the euromillions prize are practically nonexistent.** so the only thing left to do is to rely on luck.

To give a more everyday example, what is the probability that we get a 3 on a die? We know that it has 6 different numbers, so the chances of hitting our bet are reduced to:

1 / 6 x 100 = 16,66%

help me with this one, a roulette wheel like the one in casinos has 37 holes numbered from 0 to 36, find the probabilities of the following events.

a. to come out 15

b. that is a multiple of 7

c. that a number ending in 4 comes up

d. a one-digit number to come up

e. to get a number starting with 3

f. to come out a prime number

g. a divisor of 32

In college 60% of the students practice chemistry quiz, 50 % practice calculus, and 90% practice one or both. What is the probability that a college student practices both subjects?