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: 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

Answer: Option E


Question: Question: If a man crosses a 600 m long street in 5 minutes. What is his speed?

 Option A: 7 km/hr

 Option B: 7.1 km/hr

 Option C: 7.2 km/hr

 Option D: 8 km/hr

 Option E: 8.5 km/hr

Answer: Option C


Question: Question: If x and y are positive integers, and x^3*y^4 = 16, which of the following is the value of xy?

 Option A: 2

 Option B: 4

 Option C: 6

 Option D: 8

 Option E: 10

Answer:
Option A