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: It takes eight hours for a 600 km journey, if 120 km is done by train and the rest by car. It takes 20 minutes more, if 200 km is done by train and the rest by car. The ratio of the speed of the train to that of the car is?

 Option A: 3:4

 Option B: 7:6

 Option C: 1:4

 Option D: 5:4

 Option E: 2:4

Answer: Option A


Question: Question: A boat can travel with a speed of 25km/hr in still water. If the speed of the stream is 5km/hr, find the time taken by the boat to go 120km downstream.

 Option A: 1 hr

 Option B: 2 hrs

 Option C: 3 hrs

 Option D: 4 hrs

 Option E: 5 hrs

Answer: Option D


Question: Question: Factor (x + 4)3 - 9x - 36 =

 Option A: (x - 4

 Option B: (x + 6

 Option C: (x + 4

 Option D: (x + 4

 Option E: None

Answer:
Option D