##
**Probability**

### 5 Minutes Revision

**1**. The sample space of an experiment is the set of all possible outcomes of the experiment.

**2**. The sample space when a coin is tossed three times is

S = {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT}

**3**. Basic formula to find Probability of an event (E) is

Number of Favourable Outcomes | |

P(E) = | |

Total Number of Outcomes |

**4**. An event that is not very likely has a probability close to 0.

**5**. An event that is very likely has a probability close to 1 (100%).

**6**. If probability of happening an event is

**x**then probability of not happening that event is (

**1-x**).

**7**. If probability of winning a game is 0.6 then probability of loosing it is (1-0.6) = 0.4

**8**. If probability of finding a broken piece in a factory is 2 out of 7 i.e. 2/7 then probability of finding a unbroken item is (1-2/7) = 5/7

**9**. When a probability is based on data gathered from an experiment, it is called an

__or an__

**experimental probability**

**empirical probability****10**. In a deck of playing cards, there are four types of cards :

♠ (Spades in Black colour) having A, 2,3,4,5,6,7,8,9,10,J,K, and Q total 13 cards

♣ (Clubs in Black colour) having A, 2,3,4,5,6,7,8,9,10,J,K, and Q total 13 cards

♥ (Hearts in Red colour) having A, 2,3,4,5,6,7,8,9,10,J,K, and Q total 13 cards

♦ (Diamond in Red colour) having A, 2,3,4,5,6,7,8,9,10,J,K, and Q total 13 cards

**11**. Total cards = 52 cards

**12**. Jack, King and Queen are known as ‘

**Face Cards**’ , As these cards are having some pictures on it.

**13**. Note that

**Ace**is not a 'face card' as it doesn’t carry any face on it.

**14**. If one coin is tossed the total number of outcomes are 2 either a Head or a Tail.

**15**. If two coins are tossed the total number of outcomes are 2 × 2 = 4

**16**. If three coins are tossed the total number of outcomes are 2 ×2×2 = 8

**17**. Similarly for Dice, In a single roll total number of outcomes are 6

**18**. If two Dices are rolled, total number of outcomes are 6×6 = 36

**19**. Two events A and B are

**mutually exclusive**if they cannot occur at the same time.

**20**. If A and B are two mutually exclusive events, then the probability of A or B written

P (A or B) = P(A) + P(B)

Helpful......Thnq u...

ReplyDelete