## iAmCool Group Title Jose is paying for an 11$meal using bills in his wallet. He has four 1$ bills, two 5$bills, and two 10$bills. If he selects two bills at random, one at a time from his wallet, what is the probability that he will choose a 10$bill and a 1$ bill to pay for the meal? Show your work. 2 years ago 2 years ago

1. iAmCool

2. graydarl

The probability is equal to $=\frac{ 4 }{ 8 }\frac{ 2 }{ 7 }=\frac{ 1 }{ 7 }=0.142857$

3. graydarl

14.28%

4. iAmCool

o: Thanks.. :)

5. iAmCool

6. iAmCool

is*

7. graydarl

7 is because after u take out the first bill out of the total of 8 it leaves in the wallet only 7 bills. 4 is the number of $1bills and 2 the number of$10 bills

8. graydarl

Experiment 1: A card is chosen at random from a standard deck of 52 playing cards. Without replacing it, a second card is chosen. What is the probability that the first card chosen is a queen and the second card chosen is a jack? Analysis: The probability that the first card is a queen is 4 out of 52. However, if the first card is not replaced, then the second card is chosen from only 51 cards. Accordingly, the probability that the second card is a jack given that the first card is a queen is 4 out of 51. Conclusion: The outcome of choosing the first card has affected the outcome of choosing the second card, making these events dependent. Definition: Two events are dependent if the outcome or occurrence of the first affects the outcome or occurrence of the second so that the probability is changed. Now that we have accounted for the fact that there is no replacement, we can find the probability of the dependent events in Experiment 1 by multiplying the probabilities of each event. Experiment 1: A card is chosen at random from a standard deck of 52 playing cards. Without replacing it, a second card is chosen. What is the probability that the first card chosen is a queen and the second card chosen is a jack? Probabilities: P(queen on first pick) = 4 52 P(jack on 2nd pick given queen on 1st pick) = 4 51 P(queen and jack) = 4 · 4 = 16 = 4 52 51 2652 663

9. tcarroll010

It's (4/8)(2/7)(2) because you could pick the bills in either of 2 orders, so it's 2/7, not 1/7

10. graydarl
11. iAmCool

...I'm going with tcarrol010

12. graydarl

i am sorry for the mistake

13. iAmCool

It's okay:) Everyone makes mistakes. c:

14. tcarroll010

np. we all learn

15. tcarroll010

Here: in a little more detail: upcoming

16. tcarroll010

(4/8)(2/7) + (2/8)(4/7) = 2/7

17. iAmCool

After you help me with this problem.. I need help with another one.. if you don't mind.

18. tcarroll010

Have to go make pumpkin pie for tomorrow.

19. iAmCool

Oh..okay. Thanks for your help though:)

20. tcarroll010

ok

21. graydarl

i gave u a medal cause iamcool gave his mine and i didn t provide the correct answer :D

22. iAmCool