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: Kiran is younger than Bineesh by 7 years and their ages are in the respective ratio of 7:9. How old is Kiran?

 Option A: 22.5

 Option B: 24.5

 Option C: 23.5

 Option D: 25.5

 Option E: 26.5

A: Option B
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Q: Question: Rob traveled a distance of 30 km, covering the first 10 km in x minutes, the next 10 km in y minutes and the last 10 km in z minutes. If he totally took 3y minutes to cover the whole distance, then which of the following cannot be true? Assume x , y and z are different.

 Option A: z=3x

 Option B: x=3z

 Option C: y=2x

 Option D: x=2y

 Option E: y=3x

A: Option D
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Q: Question: If 8 men and 2 boys working together, can do four times as much work per hour as a man and a boy together. Find the ratio of the work done by a man and that of a boy for a given time?

 Option A: 3:2

 Option B: 2:1

 Option C: 3:3

 Option D: 1:2

 Option E: 6:1

A:
Option D
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