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: jacob is 39 years old . he is 3 times as old as his brother . how old will jacob be when he is twice as old ?
Options: a ) 63 , b ) 64 , c ) 65 , d ) 76 , e ) 67
[A]: c

[Q]: Problem: if the average ( arithmetic mean ) of a and b is 110 , and the average of b and c is 170 , what is the value of a c ?
Options: a ) 120 , b ) 100 , c ) 100 , d ) 135 , e ) it can not be determined from the information given
[A]: a

[Q]: Problem: a two - digit number is such that the product of the digits is 8 . when 18 is added to the number , then the digits are reversed . the number is :
Options: a ) 32 , b ) 24 , c ) 12 , d ) 7 , e ) 45
[A]:
b