25

Our Lesson

Embed Size (px)

DESCRIPTION

Our Lesson. Counting Principles. Warm Up. For each situation, list the total number of outcomes. Tossing a quarter and a nickel HT, HT, TH, TT; 4 2. Choosing a letter from D,E, and F, and a number from 1 and 2 D1, D2, E1, E2, F1, F2; 6 - PowerPoint PPT Presentation

Citation preview

Page 1: Our Lesson
Page 2: Our Lesson

Confidential 2

Warm Up

1. Tossing a quarter and a nickel HT, HT, TH, TT; 4

2. Choosing a letter from D,E, and F, and a number from 1 and 2

D1, D2, E1, E2, F1, F2; 6

3. Choosing a tuna, ham, or egg sandwich and chips, fries, or salad

TC, TF, TS, HC, HF, HS, EC, EF, ES; 9

For each situation, list the total number of outcomes.

Page 3: Our Lesson

Confidential 3

Determine whether the following game for two players is fair.

4. Toss three pennies. No

5. If exactly two pennies match, Player 1 wins. Otherwise, Player 2 wins. Player 1 = ¾ Player 2 = ¼

Warm Up

Page 4: Our Lesson

Confidential 4

Lets recap what we have learned in this

lesson There are two basic types of trees. • Unordered Tree• Ordered Tree

In an unordered tree, a tree is a tree in a purely structural sense

A tree on which an order is imposed — ordered Tree

A node may contain a value or a condition or represents a separate data structure or a tree of its own.

Each node in a tree has zero or more child nodes, which are below it in the tree

Page 5: Our Lesson

Confidential 5

A Sub tree is a portion of a tree data structure that can be viewed as a complete tree in itself

A Forest is an ordered set of ordered trees

Traversal of Trees

• In order• Preorder• Post order

In graph theory, a tree is a connected acyclic graph.

Page 6: Our Lesson

Confidential 6

Preorder And Post order Walk

• A walk in which each parent node is traversed before its children is called a pre-order walk;

• A walk in which the children are traversed before their respective parents are traversed is called a post-order walk.

Page 7: Our Lesson

Confidential 7

Tree diagram

The probability of any outcome in the sample space is the product (multiply) of all possibilities along the path that represents that outcome on the tree diagram. A probability tree diagram shows all the possible events.

Example: A family has three children.  How many outcomes are in the sample space that indicates the sex of the children? 

Page 8: Our Lesson

Confidential 8

There are 8 outcomes in the sample space. The probability of each outcome is 1/2 • 1/2 • 1/2 = 1/8.

Assume that the probability of male

(M) and the probability of female

(F) are each 1/2.

Page 9: Our Lesson

Confidential 9

Sample space

Sample space is the set of all possible outcomes for an experiment. An Event is an experiment.

Example:

1) Find the sample space of rolling a die.

Sample space = { 1, 2, 3, 4, 5, 6 }

2) Find the sample space of Drawing a card from a standard deck.

Sample space = { 52 cards}

3) Rolling a die, tossing a coins are events.

Let’s get Started

Page 10: Our Lesson

Confidential 10

Outcomes of an Event Definition:

Possible outcomes of an event are the results whichmay occur from any event.Example:

The following are possible outcomes of events :• A coin toss has two possible outcomes. The outcomesare "heads" and "tails".

• Rolling two regular dice, one of them red and one ofthem blue, has 36 possible outcomes.

Note: Probability of an event = number of favorable ways/ total number of ways

Page 11: Our Lesson

Confidential 11

Example

If two coins are tossed simultaneously then the possible

outcomes are 4. The possible outcomes are HH, HT, TH,

TT. The tree diagram below shows the possible outcomes.

STARTH

T

H

TH

T

Page 12: Our Lesson

Confidential 12

Counting PrincipleThe Counting Principle is MULTIPLY the number of ways each activity can occur. If event M can occur in m ways and is followed by event N that can occur in n ways, then the event M followed by N can occur in m x n ways.

Example:

A coin is tossed five times.  How many arrangements of heads and tails are possible?

Solution:

By the Counting Principle, the sample space (all possible arrangements) will be 2•2•2•2•2 = 32 arrangements of heads and tails.

Page 13: Our Lesson

Confidential 13

PermutationA permutation is an arrangement, a list of all possible

permutations of things is a list of all possiblearrangements of the things. Permutations are aboutOrdering. It says the number of permutations of a setof n objects taken r at a time is given by the followingformula: nPr = (n!) /(n - r)!  

Example: A list of all permutations of the letter ABC is

ABC, ACB, BAC, BCA, CAB, CBA

Page 14: Our Lesson

Confidential 14

CombinationCombination means selection of things. The word

selection is used, when the order of things has no

importance. The number of combinations of a set of nobjects taken r’ at a time is given by

nCr = (n!) /(r! (n -r)!)  

Example:

4 people are chosen at random from a group of 10

people. How many ways can this be done?

Solution: n= 10 and r = 4 plug in the values in the formula There are 210 different groups of people you can choose.

Page 15: Our Lesson

Confidential 15

Your turn1. _______ diagram shows all the possible events.

Tree diagram

2. Write the possible outcome if a coin is tossed?

{H, T}

3. ________is MULTIPLY the number of ways each activity can occur. Counting principle

4. How many elements are in the sample space of tossing 3 pennies? 8

5. A _______ is the set of all possible outcomes. Sample space

Page 16: Our Lesson

Confidential 16

6) _______ is an experiment. [event, outcome] event

7) ____________ is an arrangement. Permutation

8) Combination means _________ of things. Selection

9) Write the formula to find permutation.nPr = (n!) /(n - r)!. 

10) Write the formula to calculate combination.nCr = (n!) /(r! (n -r)!).  

Your turn

Page 17: Our Lesson

Confidential 17

Refreshment Time

Page 18: Our Lesson

Confidential 18

Lets play a game

http://www.miniclip.com/games/big-jump-challenge/en/

Page 19: Our Lesson

Confidential 19

1) A box has 1 red ball, 1 green ball and 1 blue ball, 2 balls are drawn from the box one after the other,without replacing the first ball drawn. Use the treediagram to find the number of possible outcomes forthe experiment .Solution:-• The possible outcomes are RG, RB, GR, GB, BG and BR. • So, the number of possible outcomes is 6.

Page 20: Our Lesson

Confidential 20

2) The ice cream shop offers 31 flavors.  You order adouble-scoop cone.  In how many different ways can

theclerk put the ice cream on the cone if you wanted twodifferent flavors?

Solution:-There are 31 flavors available for the first scoop.’There are then 30 flavors available for the secondscoop.The possibilities are = 31 * 30 = 930

Page 21: Our Lesson

Confidential 21

3) 8 students names will be drawn at random from a hat containing 14 freshmen names, 15  sophomore names, 8 junior names, and 10 senior names. How many different draws of 8 names are there overall?Solution:-

This would be a combination problem, because a draw would be a group of names without regard to order. 

There are 14 freshmen names, 15  sophomore names, 8 junior names, and 10 senior names for a total of 47 names.

Page 22: Our Lesson

Confidential 22

n Cr = n! / r! (n - r)!

Here n = 47 and r = 8 n Cr = 47! / 8! (47-8)!

= 47 * 46*45*44*43*42*41*40*39! 8! 39!

= 47 * 46*45*44*43*42*41*40*39 8 * 7* 6 * 5 * 4 * 3 * 2 * 1

= 314457495

There are 314,457,495 different draws.

Page 23: Our Lesson

Confidential 23

Event : An Event is an experiment.

Outcome: Possible outcomes of an event are

the results which may occur from any

event.

Lets review what we have

learned in our lesson

Counting principle: Counting principles

describe the total number of possibilities or

choices for certain selections.

Page 24: Our Lesson

Confidential 24

Permutation:

A permutation is an arrangement. Permutations are about Ordering.

The formula is nPr = (n!) /(n - r)!

Combination:

Combination means selection of things. Order of things has no importance.

The formula is nCr = (n!) /(r! (n -r)!)

Page 25: Our Lesson

Confidential 25

You did great in your lesson today !

Practice and keep up the good work