TASK DEFINITION: Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.
PROBLEM: Problem: if a lends rs. 3150 to b at 8 % per annum and b lends the same sum to c at 12.5 % per annum then the gain of b in a period of 2 years is ?
Options: a. 280, b. 295, c. 283.5, d. 245, e. 200

SOLUTION: c

PROBLEM: Problem: the average of first six prime numbers greater than 20 is ?
Options: a. 10, b. 20, c. 30, d. 40, e. 34

SOLUTION: e

PROBLEM: Problem: a confectioner decides to sell all of his pastry due to the coming holiday. his pastry goods are equally divided among a group of 50 regular customers. if only 49 customers come to the bakery, each one will receive 6 less pastry goods. how much pastry does the confectioner needs to sell ?
Options: a. 500., b. 412., c. 432., d. 502., e. 522.

SOLUTION:
a