## anonymous one year ago WHAT IS UP WITH PROBABILITY MAN

1. anonymous

2. anonymous

Looks like some sort of a bug in the school's system. This happens a lot in Aventa or Accelerate classes. Screenshot and email your teacher or mentor, if you have them.

3. anonymous

I need help

4. anonymous

I'm just a 9th grader, but I don't think it makes sense at all and is a mistake. What school system is that?

5. anonymous

What's the probability that Gary's name will be drawn on the first draw?

6. nincompoop

let us make this simple

7. nincompoop

it starts by learning from the very basic

8. nincompoop

if I had a coin with head and tail and I flipped it, what is the chance that it will land with its tail up?

9. anonymous

50/50

10. nincompoop

what does that mean?

11. nincompoop

50/50 = 1

12. nincompoop

okay then let us make it this way

13. nincompoop

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14. mathstudent55

When people say 50,50 they means there is a 50% chance of one event happening and 50% chance of the other event happening.

15. nincompoop

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16. nincompoop

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17. nincompoop

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18. anonymous

He had 10 out of 50 percent chance each time they drew the tickets.

19. nincompoop

do you get this simple example @Starr_DynastyT

20. nincompoop

hello

21. anonymous

just a bit

22. anonymous

1/5 times 1/5 equals .04 or 4%. You multiply the number by itself each time you draw again without taking out the tickets.

23. anonymous

By taking out tickets I mean taking them out without putting them back in.

24. anonymous

I'm getting 4

25. mathstudent55

The probability of an event happening is: $$p(even) = \dfrac{number ~of~desired~outcomes}{total~number~of~outcomes}$$ There are 10 tickets that belong to Gary. There are a total of 50 tickets. Any ticket that belongs to Gary is a desired outcome. The number of desired outcomes is 10. There are 50 possible outcomes since there are a total of 50 tickets. For the first drawing, the probability of taking out a ticket with Gary's name is: $$p(drawing~ticket~with~Garry's ~name) = \dfrac{10}{50} = \dfrac{1}{5}$$ Then the ticket is placed back in the bag, and a new drawing takes place. Since all tickets are in the bag, the second drawing is exactly the same as the first drawing, so we have: $$p(drawing~ticket~with~Garry's ~name) = \dfrac{10}{50} = \dfrac{1}{5}$$ The probability of drawing Gary's name two times in a row is the product of the individual probabilities: $$p(drawing~Gary's~name ~followed ~by ~drawing~Gary's ~name) = \dfrac{1}{5} \times \dfrac{1}{5} = \dfrac{1}{25}$$ Now we need to covert 1/25 to a percent. First, we convert 1/25 to a decimal by dividing 1 by 25. 1/25 = 0.04 We get 0.04 Then to convert a decimal to a percent, we multiply by 100 (move the decimal point two place to the right) 0.04 + 100 = 4 Answer is 4%