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: for any positive integer n , the sum of the first n positive integers equals n ( n + 1 ) / 2 . what is the sum of all the integers between 1 and 50 ? 
Options: a ) 1275 , b ) 1542 , c ) 985 , d ) 1024 , e ) 1125

A: a
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Q: Problem: the age of somu is one - third his father ' s . 10 years back he was one - fifth of his father ' s age . what is his persent age ? 
Options: a ) 11 , b ) 13 , c ) 14 , d ) 12 , e ) 20

A: e
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Q: Problem: what number times ( 1 ⁄ 4 ) ^ 2 will give the value of 4 ^ 3 ? 
Options: a ) 4 , b ) 16 , c ) 64 , d ) 256 , e ) 1024

A:
e
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