In each of the following questions, read the given statement and compare the Quantity I and Quantity II on its basis. (only quantity is to be considered) Quantity I : The ratio of speed of stream and speed of a boat is 1 : 3 respectively. If the boat can cover 420 km while travelling downstream in 7 hours, then how long would it take to cover 270 km while travelling upstream? Quantity II : Boat M can travel 400 km upstream and then 400 km downstream in total time of 18 hours. If the speed of the boat is 45 km/hr, then how long would it take boat M to only travel downstream 400 km?

For Quantity I, let the speed of the stream be x and the boat be 3x, making the downstream speed 4x, so 4x equals 420 divided by 7 which gives 4x equals 60 and x equals 15. The upstream speed is 3x minus x which is 2x, or 30 km/hr, so the time to travel 270 km upstream is 270 divided by 30 equaling 9 hours. For Quantity II, let the speed of the stream be y, giving the upstream speed as 45 minus y and downstream speed as 45 plus y, and using the total time formula of 400 divided by 45 plus y plus 400 divided by 45 minus y equals 18. Solving this equation gives y equaling 5, making the downstream speed 50 km/hr, and the time to travel 400 km downstream is 400 divided by 50 equaling 8 hours. Since 9 hours is greater than 8 hours, Quantity I is greater than Quantity II.

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