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: Which of the following CANNOT be weighed using a balance scale and these unit weights: 1, 4, 7, and 10

 Option A: 13

 Option B: 15

 Option C: 17

 Option D: 19

 Option E: 21

Answer: Option A


Question: Question: Sam is training for the marathon. He drove 12 miles from his home to the Grey Hills Park and then ran 5 miles to Red Rock, retraced his path back for 2 miles, and then ran 3 miles to Rock Creek. If he is then n miles from home, what is the range of possible values for n?

 Option A: 1 ≤ n ≤23

 Option B: 3 ≤ n ≤21

 Option C: 6 ≤ n ≤18

 Option D: 5 ≤ n ≤19

 Option E: 9 ≤ n ≤15

Answer: Option C


Question: Question: A sum of money lent out at S.I. amounts to a total of $520 after 2 years and to $820 after a further period of 5 years. What was the initial sum of money that was invested?

 Option A: $340

 Option B: $360

 Option C: $380

 Option D: $400

 Option E: $420

Answer:
Option D