# Help solve simple math problem.

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1. ### OP Devante Crescent fresh at best. Member Level 5

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Hey guys.

Sounds dumb but how do I find the probability of the following question?

A class has 32 students. Out of that class, 4 will fail.
Rudy is in this class.
What is the probability of Rudy failing?

I keep coming up with 1/8 but I think I'm missing a step.

2. ### Recorderdude Musician, Animator, Buffoon. Member Level 3

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4/32

divide both by four

1/8

it's that simple. 1/8 will fail and he has a 1/8 chance of failing. this could also be expressed as .125, 12.5% or 1:8.

3. ### s4mid4re 　 Member Level 3

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to be a little clearer, 1/8 = 1÷8
if you solve 1÷8, it becomes .125 (you can also solve by 4÷32 and get the same answer)
move the decimal 2 places to the right and you get the percentage (12.5%)
1:8 (one to eight) is the simplified ratio form. just think of the colon as a division sign.

4. ### Nathan Drake Obligations fulfilled, now I depart. Member Level 11

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I wanna say 1/256. There is a 4/32 chance that four of the students will fail. There is also a 1/32 chance that the student could be Rudy.

To account for this, you have to set it up as follows:
(4/32)(1/32) = 1/256 chance that the failed student is Ricky

I wanna go ahead and say this is wrong though. I could say how to do this perfectly if I felt like pulling out my notes from my mini-probability unit in Pre-Calculus earlier this year. Instead of people, it was dice. It was something like the odds of it being a number 1 - 3 in six rolls, and how many times the number 2 would show up and crap like that.

Take my answer with a grain of salt, or a shaker, or a factory full.

5. ### s4mid4re 　 Member Level 3

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I don't think that's what's being asked. If my interpretation is correct, this would be a variant of the question:
One of the 4 students that are failing can be Rudy, out of a total of 32 students. What is the probability that Rudy is 1 of the 4 students?

6. ### SinHarvest24 Shiroyasha Member Level 2

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you were just over-thinking things ^

The answer you got is correct. So is everyone else here.

7. ### OP Devante Crescent fresh at best. Member Level 5

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Thanks guys. :>

8. ### wasim ♫ Music addict ♫ Member Level 3

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looks like there are many maths genius here

( solution for my homeworks is here )

9. ### CarbonX13 GBAtemp 台灣人 Member Level 2

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Um... this really takes nothing more than what you learn in maybe grade 4 elementary school...

10. ### wasim ♫ Music addict ♫ Member Level 3

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i learned this in 6th grade

11. ### Chhotu uttam DOH HO HO HO Member Level 4

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but i learned it in 9th grade.(joking)

12. ### Nathan Drake Obligations fulfilled, now I depart. Member Level 11

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I didn't start to learn how to add, subtract, multiply, and divide fractions until pre-algebra. Through elementary school, it was pretty much all basic shit and memorizing stuff you'll never need to memorize again.

13. ### chris888222 GBAtemp's Flygon Fan Member Level 6

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Darn my math sucks :/

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Here ya go

15. ### SamAsh07 GBAtemp Addict Member Level 5

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^ You forgot to state - use magnets for faster calculation AND Math question writing teachers will go bankrupt.

16. ### CarbonX13 GBAtemp 台灣人 Member Level 2

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Maybe it's the States then. I learned how to divide, multiply, add, and subtract factions in grade 4, and BEDMAS and such by grade 5.

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