You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Input: Consider Input: Question: The banker's discount on Rs. 1600 at 10% per annum is the same as true discount on Rs. 1680 for the same time and at the same rate. The time is :

Option A: 2 months

Option B: 4 months

Option C: 6 months

Option D: 7 months

Option E: None

Output: Option C

Input: Consider Input: Question: What is the area of an equilateral triangle whose one side length is 80?

Option A: 8003

Option B: 10003

Option C: 12003

Option D: 14003

Option E: 16003

Output: Option E

Input: Consider Input: Question: A box contains 12 mangoes out of which 4 are spoilt. If four mangoes are chosen at random, find the probability that A number is selected at random from first thirty natural numbers. What is the chance that it is a multiple of either 3 or 13?

Option A: 17/30

Option B: 2/5

Option C: 11/30

Option D: 4/15

Option E: 7/15
Output: Option B