1.) 3/4 = x/96 2.) x/(x + 4) = 2/x Bellwork 4/11 3.) What is 25% of 64? 4.) 24 is 75% of what #

Bellwork 4/11 1.) 3/4 = x/96 4x = 288 x = 72

2.)x/(x + 4) = 2/x x2 = 2(x + 4) x2 = 2x + 8 x2 - 2x - 8 = 0 Bellwork 4/11 2.)x/(x + 4) = 2/x x2 = 2(x + 4) x2 = 2x + 8 x2 - 2x - 8 = 0

x2 - 2x - 8 = 0 (x - 4)(x + 2) = 0 x - 4 = 0 & x + 2 = 0 Bellwork 4/11 x2 - 2x - 8 = 0 (x - 4)(x + 2) = 0 x - 4 = 0 & x + 2 = 0 x = 4 & x = -2

____ is 25% of 64 x = 25 • .01 • 64 x = .25 • 64 x = 16 Bellwork 4/11 3.) What is 25% of 64? ____ is 25% of 64 x = 25 • .01 • 64 x = .25 • 64 x = 16

24 is 75% of ____. 24 = 75 • .01 • x 24 = .75x 32 = x Bellwork 4/11 4.) 24 is 75% of what # 24 is 75% of ____. 24 = 75 • .01 • x 24 = .75x 32 = x

Quiz 11.2

To be able to determine the probability of an event occurring. Today’s Objective To be able to determine the probability of an event occurring.

Probability Probability of an event is a Number between 0 and 1. Tell you neighbor what a probability of an event is.

Probability Will not happen Sure Thing 1

Probability of getting a head when flipping a coin. 0.5 1

Probability The probability P, of an event is the RATIO of successful outcomes, called Successes, to all outcomes of the event, called Possibilities. In other words…..

Number of Possibilities Probability Number of Successes P = Number of Possibilities

Probability An algebra Class has 17 boys and 16 girls. One student is chosen at random. The Probability that the student is a girl is: Number of girls P = Number of students

Probability # of students = 16 + 17 # of students = 33 # of girls = 16

Probability What is the probability of getting a head when a coin is flipped? # of heads = 1 # of sides of coin = 2 P = 1/2 = .5

Probability If a coin is flipped 100 times, what is the probability of getting a head on the 101st flip? Same as the first flip P = 1/2 = .5

Probability If a dice is rolled, what is the probability of getting a 4 on top? # of 4’s = 1 # of sides of dice = 6 P = 1/6

Probability # of ways to get 4 = # of total possibilities = P = ? If two die are rolled, what is the probability of getting a total of 4 on the 2 die? # of ways to get 4 = # of total possibilities = P = ?

Probability # of ways to get 4 = (2+2), (1+3), (3+1) # of total possibilities = Write the #’s from 2 -12 on your paper. Why not 1?

Probability 2 = 3 = 4 = 5 = 6 = 7 = 8 = 9 = 10 = 11 = 12 = 6 1 5 2 7 = 8 = 9 = 10 = 11 = 12 = 6 1 5 2 Total 3 4 4 3 5 36 2 1

Probability P = 3/36 = 1/12 = .083 # of ways to get 4 = (2+2), (1+3), (3+1) 3 # of total possibilities =36 P = 3/36 = 1/12 = .083

Probability 80 80 FW 160 360 If a parachutist jumps out of a plane, what is the probability the he will land on the emblem of a Football Field?

Probability The parachutist guarantees that he will land on the field or the jump is at NO cost. Area of Emblem=(80)(80) Area of field = (160)(360)

Probability P = (80)(80)/(160)(360) P = 6400/57,600 P = 1/9

Probability ~ Your Turn A jar contains 12 blue , 8 green, and 5 red marbles If you reach in & choose 1 What is the P it is blue? What is the P it is not blue? What is the P it is not black?

Probability ~ Your Turn What is the P it is blue? P = 12/25 = .48 What is the P it is not blue P = 13/25 = .52 What is the P it is not black P = 25/25 = 1

The Birthday Problem What is the probability that in a class of 23 students at least 2 were born on the same day?

Probability Experiments Rules: 1.) Pick up the materials. 2.) Make a table of Tally marks. 3.) Write the results.

Probability Experiments 1.) Throw 2 dice (100 rolls) 2.) Pay your Bill (52 weeks) 3.) Catching the Counterfeiter (1 - 25) 4.) Red, Green, or Blue (1-100)

Probability Experiments 1.) Throw 2 dice 2 - 12 2.) Pay your Bill 1 - 52 3.) Catching the Counterfeiter 1 - 25

Classwork Do the worksheet 11.2 Homework page 584 (7 - 10) Test Friday Chapter 11 11.1, 11.2, 11.4

Probability