TASK DEFINITION: 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: Problem: the age of somu is one - third his father ' s . 10 years back he was one - fifth of his father ' s age . what is his persent age ? 
Options: a ) 11 , b ) 13 , c ) 14 , d ) 12 , e ) 20

SOLUTION: e

PROBLEM: Problem: if a person walks at 14 km / hr instead of 10 km / hr , he would have walked 20 km more . the actual distance traveled by him is : 
Options: a ) 50 km , b ) 56 km , c ) 60 km , d ) 70 km , e ) 80 km

SOLUTION: a

PROBLEM: Problem: a cement mixture is composed of 3 elements . by weight , 1 / 2 of the mixture is sand , 1 / 5 of the mixture is water , and the remaining 15 pounds of the mixture is gravel . what is the weight of the entire mixture in pounds ? 
Options: a ) 30 , b ) 40 , c ) 50 , d ) 60 , e ) 80

SOLUTION:
c