TASK DEFINITION: The task is to generate the correct answer for a given math problem.
PROBLEM: Problem: what is the probability of getting a queen or spade from a set of cards ?

SOLUTION: 4 / 13

PROBLEM: Problem: in a circuit board factory , all circuit boards that pass a verification process are certified . every board that fails the verification process is indeed faulty , but 1 / 8 of those that pass are also faulty . approximately how many faulty circuit boards exist in a group of 3,200 circuit boards where 64 fail inspection ?

SOLUTION: 456

PROBLEM: Problem: a man is 20 years older than his son . in two years , his age will be twice the age of his son . the present age of the son is ?

SOLUTION:
18