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'.

Problem: if 7 a - 3 b = 10 b + 50 = - 12 b - 2 a , what is the value of 9 a + 9 b ? 
Options: a ) - 9 , b ) - 6 , c ) 0 , d ) 6 , e ) 9
c

Problem: the average age of 7 men increases by 4 years when two women are included in place of two men of ages 26 and 30 years . find the average age of the women ? 
Options: a ) 42 , b ) 40 , c ) 30 , d ) 18 , e ) 11
a

Problem: the smallest number which when diminished by 8 , is divisible 8 , 16 , 24 , 32 and 40 is : 
Options: a ) 1008 , b ) 1015 , c ) 488 , d ) 490 , e ) 590

c