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: A train passes a station platform in 36 sec and a man standing on the platform in 20 sec. If the speed of the train is 54 km/hr. What is the length of the platform?

 Option A: 229

 Option B: 240

 Option C: 288

 Option D: 277

 Option E: 221
[A]: Option B


[Q]: Question: Rs.8000 become Rs.11256 in a certain interval of time at the rate of 5% per annum of C.I. Find the time?

 Option A: 6 YEARS

 Option B: 7

 Option C: 5

 Option D: 3

 Option E: 4
[A]: Option B


[Q]: Question: In expressing a length 81.475 km as nearly as possible with three significant digits, find the percentage error?

 Option A: 0.075%

 Option B: 0.156%

 Option C: 0.031%

 Option D: 0.048%

 Option E: 0.152%
[A]:
Option C