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: gold is 10 times as heavy as water and copper is 6 times as heavy as water . in what ratio should these be mixed to get an alloy 8 times as heavy as water ? 
Options: a ) 3 : 2 , b ) 1 : 1 , c ) 3 : 1 , d ) 5 : 2 , e ) 4 : 3

Answer: b


Question: Problem: 1 , 6 , 16 , 31 , 51 , ( . . . . ) 
Options: a ) 61 , b ) 66 , c ) 76 , d ) 86 , e ) 83

Answer: b


Question: Problem: find the lowest positive integer that can be divided by all the even numbers between 14 and 21 . 
Options: a ) 4581 , b ) 5040 , c ) 3682 , d ) 1231 , e ) 1563

Answer:
b