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2011 hsc mx1 marathon (3 Viewers)

Vidhya

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Find the probability that of 5 cards chosen from a 52-card deck that 2 will be of the same suit.
I got 12/52 + 12/51 + 12/50 + 12/49 = 0.9509
Probably very wrong, but would you mind giving me the solution?
 

someth1ng

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I was off by .05 :D but how did you get one? sorry i'm a bit slow with probability
There's 4 suits - if you pick 5 cards then there must be one pair since the most spreaded result is one of each suit + 1 more card - there must be a pair.
 

nightweaver066

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I was off by .05 :D but how did you get one? sorry i'm a bit slow with probability
There are only 4 suits so it is impossible to pick 5 different suits meaning the probability of getting two cards of the same suit is 1 lol.
 

Vidhya

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Ohhh, I feel stupider now than when I posted the wrong answer :p thanks guys!
 

barbernator

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There are only 4 suits so it is impossible to pick 5 different suits meaning the probability of getting two cards of the same suit is 1 lol.
BUT!!! what if the question asks for 2 only, not 3, 4 or 5 of the same suit, then there would be a probability less than one, but the question doesn't specify, so im just being difficult
 

Sanical

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On a building construction site, an object falls from a crane in a vertical straight line. The object passes a 2 metre high windows in a time interval of one tenth of 1 second.
Find the height above the top of the window from which the object was dropped
Take g = 9.8
 

SImon05089

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^ correct me if im wrong, the height above the top of the window = 19.42 metres (2dp)
 

SImon05089

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>.> i thought u made it up!

new quick question:

if y = 10^x, find dy/dx when x = 1
 

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