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.
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Question: Question: A reduction of 20% in the price of salt enables a lady to obtain 25 kgs more for Rs.100, find the original price per kg?

 Option A: 6

 Option B: 1

 Option C: 5

 Option D: 4

 Option E: 7

Answer: Option B


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: In a certain city each of 17 Girl Scout troops is represented by a colored flag. Each flag consists of either a single color or a pair of two different colors. If each troop has a different flag, what is the minimum number of colors needed for the flags. (Assume that the order of colors in a pair on a flag does not matter.)

 Option A: 5

 Option B: 10

 Option C: 6

 Option D: 20

 Option E: 40

Answer:
Option C