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 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


[Q]: Question: The number of arrangements that can be made with the letters of the word COPY so that the vowels occupy the even places?

 Option A: 6

 Option B: 144

 Option C: 777

 Option D: 992

 Option E: 221
[A]: Option A


[Q]: Question: The captain of a cricket team of 11 members is 26 years old and the wicket keeper is 11 years older. If the ages of these two are excluded, the average age of the remaining players is one year less than the average age of the whole team. What is the average age of the team?

 Option A: 23 years

 Option B: 24 years

 Option C: 25 years

 Option D: 26 years

 Option E: 27 years
[A]:
Option E