From ae33d5888fb12a5cc71e5f6f8668f1daab064c2c Mon Sep 17 00:00:00 2001 From: Anas Salam <38077746+anassalam@users.noreply.github.com> Date: Tue, 25 Jun 2019 03:24:03 +0500 Subject: [PATCH] Probability index.md file updated (#27836) index.md file updated with more info, some examples and cases. --- .../english/mathematics/probability/index.md | 45 ++++++++++++++++++- 1 file changed, 44 insertions(+), 1 deletion(-) diff --git a/guide/english/mathematics/probability/index.md b/guide/english/mathematics/probability/index.md index b800723266..196d1e1029 100644 --- a/guide/english/mathematics/probability/index.md +++ b/guide/english/mathematics/probability/index.md @@ -5,7 +5,50 @@ title: Probability The probability of an event is the chance that an event is going to occur. - Probabilities generally range from 0 to 1, with 0 indicating that an event will never happen and 1 that an event will happen for certain. + Probabilities generally range from 0 to 1, with 0 indicating that an event will never happen and 1 that an event will happen for certain.
+ + The total of all probabilities will always sum up to 1.
+ If the probability of a event happening is 0.75, then the probability of an event NOT happening will be 1 - 0.75 = 0.25, (the event not happening is calculated as reverse of this event happening). + +Example 1:
+ A coin has 2 sides, (Head and Tail).
+ When an unbaised coin is flipped, there are 2 possibilities. The chances of Head appearing is 1/2 and similarly a Tail appearing is 1/2.
+ The total of all outcomes will always be equal to 1, like in this case 1/2 + 1/2 = 1. + + Example 2:
+ A dice has 6 sides, (1, 2, 3, 4, 5 and 6).
+ When an unbaised dice is rolled, each side has a probability of 1/6 or (0.1667) appearing.
+ Similarly in this example too, the total of all outcomes will be 1, (0.1667 + 0.1667 + 0.1667 + 0.1667 + 0.1667 + 0.1667 = 1). + + 
+  Case 1:
+  chances of an odd number appearing is 3/6, (1, 3 and 5).
+  
+  Case 2:
+  chances of number 6 NOT appearing is 5/6, (1 - 1/6).
+
+ + Example 3:
+ A standard deck of cards has 52 cards, consisting of 4 suits - 2 Red suits (Hearts ♥ and Diamonds ♦) and 2 Black suits (Spades ♠ and Clubs ♣). And each suit has 13 cards with an Ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen and King.
+ The probability of each card being withdrawn is 1/52.
+ + 
+  Case 1:
+  chances of a Red card being randomly drawn from a standard deck of cards is 26/52, (13 Diamonds + 13 Hearts = 26 total Red).
+  
+  Case 2:
+  chances of number 5 appearing is 4/52, (one from each Suit).
+  
+  Case 3:
+  chances of Ace of Spades appearing is 1/52, (only 1 Ace in Spades Suit).
+  
+  Case 4:
+  chances of a Face card appearing is 12/52, (3 Face cards in each Suit namely Jack, Queen and King)
+  
+  Case 5:
+  chances of 8 of Hearts NOT appearing is 0.98, (1 - 1/52).
+
+