In day to day life, we need many things. If things are big so we need a big budget for that.

We need probable cost to purchase a thing.

For the construction of a building, we need money to purchase materials & other miscellaneous items.

So we estimate the probable cost of building to arrange the money we need.

But in mathematics probability is different.

# What is Probability?

Probability is the game of chances. When we toss a coin chance of getting a total of two answers

**head**or**tail**.If we toss a coin once so the probability of getting head is 1/2 & probability of getting tail is 1/2.

Here 1 shows the number of outcomes for head or tail & 2 shows total outcome the the

Probability is denoted by P(E).

Where P = Probability & E = Event

## Formula of Probability

P(E) = (Outcomes favourable to any event E) ÷ (Total outcomes of the experiment)

## Example of Probability

First, we throw a dice (Ludo cube) so chances of getting answers are six. It may be 1, 2, 3, 4, 5, 6.

Let we get result 4 on the top face. So the number of outcomes for event 4 is 1 after throwing a dice.

And chances of getting total outcomes is 6 (maybe 1,2,3,4,5,6).

So the probability of event P(4) = (1÷6).

Where,

1 = No. of times 4 is coming

& 6 = Total outcomes of experiment

## Problems of Probability

**1.) A bag contains a red ball, a blue ball & a yellow ball, all the balls being of the same size. A man takes out a ball from the bag without looking into it. What is the probability that she takes out a blue ball?**

Solve:

Total chances of getting the ball from the bag are 3

*(maybe red, blue or yellow ball)*

*(Outcomes favourable to the blue ball is 1)*

And we need to find the probability of the blue ball.

On putting the values the in formula-

So the probability of blue ball P(B) = (1÷3)

Or

P(B) = 1/3

**2.) We throw a dice once. So what is the probability of getting a number less than four?**

Solve:

In the dice total number of outcomes is

**6***(maybe be 1,2,3,4,5 or 6)*

And the number of outcomes favourable to less than 4 is

**3**(*maybe 1,2 or 3)*

On putting the values in the formula-

Probability of event less than four P(E) = (3÷6)

Or

P(E) = 1/2