Question

Retest: ProbabilityFor problems 1-3: Johnny Awesome has three red marbles, two blue marbles, 5 green marbles, and 7 yellowmarbles in a bag. What is the probability that Johnny....

Answer 1

We have

3 red marbles

2 Blue

5 green

7 yellow

Total marbles is

T= 3+2+5+7= 17

T=17

1)Probability draws a red marble

is given by

`P(r)=(Red)/(total)`
`P(r)=(3)/(17)`
`P(r)=(3)/(17)=0.1764`

2)Draws yellow replace it then draws blue

Draws yellow probability is given by

`P(y)=(7)/(17)`

when the text says replace it means we have the same total number of marbles

Draws blue probability is given by

`P(b)=(2)/(17)`

then the probability of Draws yellow replace it then draws blue is

`P(yb)=P(y)*p(b)`
`P(yb)=(7)/(17)*(2)/(17)`
`P(yb)=(14)/(289)=0.048`

c)Draws blue marble, does not replace it then draws green marble

probability of draws blue

`P(b)=(2)/(17)`

since we do not replace the marble the new total of marbles is 16

then

the probability of draw a green is

`p(g)=(5)/(16)`

then

Draws blue marble, does not replace it then draws green marble

`p(bg)=p(b)*p(g)`
`p(bg)=(5)/(136)=0.036`