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Probability Question (1 Viewer)

mizz_smee

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thats not the five ways 20 20 is less then 45
are u sure u do maths ?
its 20 25
20 25
25 20
25 20
25 25
they are the five ways

EDIT: just read it again
i get what ur saying now
 

maddison10

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Sweet_Lemon

im guessing u meant

20 25

25 20

25 25

cause thats wat i did, same answer... seemed logical to me...
 

Purp|e

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hmmm does the big number u all seem to be getting simplifiy ???!?! cus i got a big number over a big number but it simplified :| rofl ... maybeh i got rong :S
 

Sweet_Lemon

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mizz_smee said:
thats not the five ways 20 20 is less then 45
are u sure u do maths ?
its 20 25
20 25
25 20
25 20
25 25
they are the five ways

EDIT: just read it again
i get what ur saying now

PPLSZZZZ~~ ok....i can't put the pic i just made..it's like there's 5 strokes between them...not the 20 20 one though...but the rest...i know tat this looks funny but tat's how the past questions drew it.... its the same way as u guyz explaining...ekekek
 

DI2AGON

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errm... u draw the table of the 36 possibilities, for two dice it's 36x36 possible outcomes, however only four of them produce an added amount of 45

so the answer was 1 - 5/36x36
 
Last edited:

ftr10

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you made me guys happy :D

1291/1296....

me too, three, four...kakaka

prob of =50 ie (5x5) two times (1/36)^2
prob of =45 ie (4x5) two times (2/36)^2

therefore, 1-(1/36)^2-(2/36)^2

= 1291/1296

phew...maybe theres hope for 110/120...
 

~ ReNcH ~

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1291/1296 - better be, coz that's what I got.

I think I said there were three cases where the sum >= 45: 20/25, 25/20, 25/25
P(20) = 1/18
P(25) = 1/36

.'. P(sum <45) = 1 - (1/18x1/36 + 1/36x1/18 + 1/36x1/36)
= 1 - 5/1296
= 1291/1296

Am I right - at least it's only worth 2 though??
 

acmilan

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This question was the only one i initially thought i got wrong but apparantly most people got 1291/1296 which is what i got
 

monkey187

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Sweet_Lemon said:
let me see...should be

P(<45) = 1 - [ (1/36 *1/36) + (1/36 * 2/36*) + (2/36 * 1/36) ]

think tat's how i wrote it...

yeh i did it that way 2 i dont remember my answer tho :( sumtin over 1xxx :p hopefully right
 

Sweet_Lemon

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monkey187 said:
yeh i did it that way 2 i dont remember my answer tho :( sumtin over 1xxx :p hopefully right
GOOD LUCK...u well be fine...won't deduct on calculation i think~~
 

Acid

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Not sure if anyone has said this yet but I think the answer is:

1 - P(Sum isn't less than 45)
=
1 - (1/36 * 1/36)
=
1 - 1/1296
= 1295/1296
 

skankit

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im pretty sure i got that, well at least i had the same working, so i would get it, right?

if i didnt i am very stupid. which is also likely :eek:
 

Acid

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ftr10 said:
you made me guys happy :D

1291/1296....

me too, three, four...kakaka

prob of =50 ie (5x5) two times (1/36)^2
prob of =45 ie (4x5) two times (2/36)^2

therefore, 1-(1/36)^2-(2/36)^2

= 1291/1296

phew...maybe theres hope for 110/120...
4x5 isn't greater than 45 man... i'm not sure that mine is right but your way looks wrong..
 

~ ReNcH ~

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Acid said:
Not sure if anyone has said this yet but I think the answer is:

1 - P(Sum isn't less than 45)
=
1 - (1/36 * 1/36)
=
1 - 1/1296
= 1295/1296
But you haven't considered 20+25, which can happen twice.
 

mitch_07

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will u get a carried error if u put 5/72 as i added 36+36 instead of 36*36
 

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