In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: what is 2 3 / 4 - 1 2 / 5 divided by 2 / 3 - 1 / 3 ? 
Options: a ) 17 / 36 , b ) 36 / 17 , c ) 7 / 6 , d ) 27 / 20 , e ) 51 / 44

A: d
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Q: Problem: pure milk costs 3.60 per litre . a milkman adds water to 25 litres of pure milk and sells the mixture at 3 per litre . how many litres of water does he add ? 
Options: a ) 2 litres , b ) 5 litres , c ) 7 litres , d ) 11 litres , e ) none of these

A: b
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Q: Problem: the sum of the present age of henry and jill is 40 . what is their present ages if 11 years ago henry was twice the age of jill ? 
Options: a ) and 27 , b ) and 24 , c ) and 23 , d ) and 29 , e ) of these

A:
c
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