TASK DEFINITION: The task is to generate the correct answer for a given math problem.
PROBLEM: Problem: what decimal fraction is 90 ml of a litre ?

SOLUTION: . 09

PROBLEM: Problem: if 1.5 cm of a pencil is purple , 0.5 cm of the remaining is black and the remaining 2 cm is blue , what is the total length of the pencil ?

SOLUTION: 4 cm

PROBLEM: Problem: the average age of father and his two sons is 24 years . 5 years ago , the average age of the two sons was 15 years . if the difference between the ages of the two sons is 4 years , what is the present age of the father ?

SOLUTION:
32