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.

Q: Question: A student gets 60% in one subject, 80% in the other. To get an overall of 75% how much should get in third subject.

 Option A: 75%

 Option B: 25%

 Option C: 85%

 Option D: 55%

 Option E: 65%

A: Option C
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Q: 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

A: Option D
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Q: Question: If the cost of 8 erasers and 5 sharpeners is Rs.31/-, what will be the cost of 24 erasers and 10 sharpeners?

 Option A: Rs.62/-

 Option B: Rs.84/-

 Option C: Rs.78/-

 Option D: Rs.150

 Option E: None of these

A:
Option C
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