In this task, you need to provide the correct option for a given problem from the provided options.

Q: Problem: a certain business school has 500 students , and the law school at the same university has 800 students . among these students , there are 30 sibling pairs consisting of 1 business student and 1 law student . if 1 student is selected at random from both schools , what is the probability that a sibling pair is selected ? 
Options: a ) 3 / 40000 , b ) 3 / 20000 , c ) 3 / 4000 , d ) 9 / 400 , e ) 6 / 130

A: a
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Q: Problem: the ratio of the number of females to males at a party was 1 : 2 but when 7 females and 7 males left , the ratio became 1 : 3 . how many people were at the party originally ? 
Options: a ) 28 , b ) 32 , c ) 36 , d ) 42 , e ) 50

A: d
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Q: Problem: a certain bag contains 60 balls — 22 white , 10 green , 7 yellow , 15 red , and 6 purple . if a ball is to be chosen at random , what is the probability that the ball will be neither red nor purple ? 
Options: a ) 0.09 , b ) 0.65 , c ) 0.54 , d ) 0.85 , e ) 0.91

A:
b
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