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 the least whole number that should be added to 784839 if it is to be divisible by 10 ? 
Options: a ) 3 , b ) 2 , c ) 1 , d ) 5 , e ) 6

A: c
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Q: Problem: a ’ s speed is 20 / 19 times that of b . if a and b run a race , what part of the length of the race should a give b as a head start , so that the race ends in a dead heat ? 
Options: a ) 1 / 19 , b ) 3 / 19 , c ) 1 / 10 , d ) 1 / 20 , e ) 3 / 10

A: d
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Q: Problem: the difference of two numbers is 11 . one third of their sum is 7 . what are the two numbers ? 
Options: a ) 21,10 , b ) 16,5 , c ) 3,14 , d ) 11,10 , e ) 7,14

A:
b
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