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.
--------
Question: Question: A set of numbers has the property that for any number t in the set,t+3 is in the set. If -2 is in the set, which of the following must also be in the set? I. -3 II. 1 III. 4

 Option A: I,III only

 Option B: III only

 Option C: II only

 Option D: II,III only

 Option E: I only

Answer: Option D


Question: Question: If a committee of 2 people is to be selected from among 5 married couples so that the committee does not include two people who are married to each other, how many such committees are possible?

 Option A: 20

 Option B: 40

 Option C: 50

 Option D: 80

 Option E: 120

Answer: Option B


Question: Question: The price of a integrated declines by 67 percent every 6 months. At this rate, approximately how many years will it take for the price of an $81 integrated chip to reach $1?
81- 67% * 81 = 27 approx
27 - 0.67*27 = 9 approx
9- 0.67*9 = 3 approx
3-0.67*3= $1 approx

 Option A: 1.5 years

 Option B: 2 years

 Option C: 3 years

 Option D: 13 years

 Option E: 13.5 years

Answer:
Option B