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: The average expenditure of a labourer for 6 months was 90 and he fell into debt. In the next 4 months by reducing his monthly expenses to 60 he not only cleared off his debt but also saved 30. His monthly income i

 Option A: 70

 Option B: 72

 Option C: 75

 Option D: 78

 Option E: 81

A: Option E
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Q: Question: The ratio between the speeds of two trains is 7 : 8. If the second train runs 400 kms in 4 hours, then the speed of the first train is:

 Option A: 70 km/hr

 Option B: 75 km/hr

 Option C: 84 km/hr

 Option D: 87.5 km/hr

 Option E: 88.5 km/hr

A: Option D
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Q: Question: Mr. Karan borrowed a certain amount at 6% per annum simple interest for 9 years. After 9 years, he returned Rs. 8010/-. Find out the amount that he borrowed.

 Option A: s. 5266

 Option B: s. 5269

 Option C: s. 5228

 Option D: s. 5201

 Option E: s. 52192

A:
Option D
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