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

Q: Problem: the probability that a computer company will get a computer hardware contract is 4 / 5 and the probability that it will not get a software contract is 3 / 5 . if the probability of getting at least one contract is 9 / 10 , what is the probability that it will get both the contracts ? 
Options: a ) 1 / 8 , b ) 2 / 9 , c ) 3 / 10 , d ) 4 / 11 , e ) 5 / 12

A: c
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Q: Problem: how many kilograms of pure water is to be added to 100 kilograms of a 30 % saline solution to make it a 10 % saline solution . 
Options: a ) 100 , b ) 200 , c ) 300 , d ) 400 , e ) 500

A: b
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Q: Problem: a certain fraction has the same ratio to 1 / 18 , as 2 / 5 does to 7 / 9 . what is this certain fraction ? 
Options: a ) 1 / 20 , b ) 1 / 25 , c ) 1 / 30 , d ) 1 / 35 , e ) 1 / 40

A:
d
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