**Published :**Monday, 25 September, 2017 11:36 AM

The Quantitative Ability section of CAT 2017 is very important for scoring a good percentile. It has questions from almost all section of maths. Below we are providing important formulas from one such important section - Probability. It will beneficial for your CAT 2017 preparation as well as for last minute revision.

**Important Formulas:**

**Experiment:**An operation which can produce some well-defined outcome is called an experiment.**Random Experiment:**An experiment in which all possible outcomes are known and the exact output cannot be predicted in advance is called a random experiment.

**Examples:**- Rolling an unbiased dice.
- Tossing a fair coin.
- Drawing a card from a pack of well-shuffled cards.
- Picking up a ball of certain color from a bag containing balls of different colors.

**Details:**- When we throw a coin, then either a Head (H) or a Tail (T) appears.
- A dice is a solid cube, having 6 faces, marked 1, 2, 3, 4, 5, 6, respectively.

When we throw a dice, the outcomes is the number that appears on its upper faces. - A pack of cards has 52 cards.

It has 13 cards of each suit; name –

**Spades, Clubs, Hearts and Diamonds.**Cards of spades and clubs are

**black cards**.Cards of hearts and diamonds are

**red cards**.There are four honors of each unit.

There are

**King, Queens, and Jacks.**These are all called**face cards.**

**Sample Space:**When we perform an experiment, then the set S of all possible outcomes is called the**sample space.**

**Example:**- In tossing a coin, S = {H, T}.
- If two coin are tossed, the S = {HH, HT, TT, TH}.
- In rolling a dice, we have, S = { 1, 2, 3, 4, 5, 6}.

**Event:**Any subset of a sample space is called an

**event**.**Probability of Occurrence of an Event:**Let S be the sample and let E be an event.

### Attempt 100 Mock Questions on QA Now

Stay informed, Stay ahead and stay inspired with

__MBA Rendezvous__