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: a is the hundreds digit of the 3 digit integer x , b is the tens digit of x , and c is the units digit of x . 4 a = 2 b = c , and a > 0 . what is the difference between the two greatest possible values of x ? tip : dont stop till you have exhausted all answer choices to arrive at the correct one . 
Options: a ) 124 , b ) 297 , c ) 394 , d ) 421 , e ) 842

A: a
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Q: Problem: if 15 ! / 3 ^ x is an integer , what is the greatest possible value of x ? 
Options: a ) 3 , b ) 4 , c ) 5 , d ) 6 , e ) 7

A: d
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Q: Problem: the total age of a and b is 11 years more than the total age of b and c . c is how many year younger than 
Options: a ) 14 years , b ) 12 years , c ) 56 years , d ) 66 years , e ) 11 years

A:
e
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