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'.
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Question: Problem: a student chose a number , multiplied it by 8 , then subtracted 138 from the result and got 102 . what was the number he chose ?
Options: a ) 30 , b ) 120 , c ) 130 , d ) 140 , e ) 150

Answer: a

Question: Problem: what is the remainder when 1003 * 1005 * 1007 is divided by 15
Options: a ) 3 , b ) 17 , c ) 14 , d ) 0 , e ) 7

Answer: d

Question: Problem: if x , y , and z are positive integers , and 3 x = 5 y = 6 z , then the least possible value of x + y + z is
Options: a ) 21 , b ) 28 , c ) 37 , d ) 42 , e ) 60

Answer:
a