The task is to generate the correct answer for a given math problem.

Input: Consider Input: Problem: virginia , adrienne , and dennis have taught history for a combined total of 96 years . if virginia has taught for 9 more years than adrienne and for 12 fewer years than dennis , for how many years has dennis taught ?

Output: 4

Input: Consider Input: 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 ?

Output: 456

Input: Consider Input: Problem: find the area of trapezium whose parallel sides are 28 cm and 18 cm long , and the distance between them is 15 cm .
Output: 345