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: if a ( a + 2 ) = 99 and b ( b + 2 ) = 99 , where a ≠ b , then a + b = 
Options: a ) - 2 , b ) - 5 , c ) - 8 , d ) - 10 , e ) - 12

Answer: a


Question: Problem: 5 years ago , the average age of a , b , c and d was 45 years . with e joining them now , the average of all the 5 is 50 years . the age of e is ? 
Options: a ) 50 , b ) 47 , c ) 48 , d ) 49 , e ) 46

Answer:
a