A dinghy rower crossing the lake

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A dinghy rower crossing the lake

by gmatdriller » Sat Aug 07, 2010 6:53 am
A dinghy rower crossing the lake approached a distance-marking buoy on the route that said
"42" on the side facing him and "44" on the reverse. He thought the next buoy would show
that he was exactly at the midpoint of the route. However, the next buoy actually said "41"
facing him, and "45" behind.

Which of the following, if true, would explain the paradox above?

A) The second buoy's numbers were reversed.

B) The buoys' numbers are denominated in nautical miles instead of land miles.

C) The numbers facing him represent miles left to the end of the route, not miles from the beginning.

D) Between the two buoys the rower saw, one was missing.

E) Originally, the buoys had been built for use by sailboats, not rowboats.

how do we reason this?

Answer: C
Last edited by gmatdriller on Sat Aug 07, 2010 1:01 pm, edited 1 time in total.
Source: — Critical Reasoning |

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by selango » Sat Aug 07, 2010 8:21 am
A dinghy rower crossing the lake approached a distance-marking buoy on the route that said "42" on the side facing him and "44" on the reverse. He thought the next buoy would show that he was exactly at the midpoint of the route. However, the next buoy actually said "41" facing him, and "45" behind.

Which of the following, if true, would explain the paradox to the left?

A) The second buoy's numbers were reversed.

B) The buoys' numbers are denominated in nautical miles instead of land miles.

C) The numbers facing him represent miles left to the end of the route, not miles from the beginning.

D) Between the two buoys the rower saw, one was missing.

E) Originally, the buoys had been built for use by sailboats, not rowboats.
--Anand--

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by selango » Sat Aug 07, 2010 8:33 am
Buoy said "42" on the facing side and "44" on the reverse.

when approaching this buoy the rower thought that it reprsent the distance from the begining.So the rower assumes if he/she covers one more mile/km,the distance ll reads "43" which is the midpoint of the route.

What the rower assumes here?The facing side distance increases and reverse side decreases.

However next buoy read "41" on facing side and "45" behind?

How can we resolve this paradox?

If we assumes that the distance on the bouy is the distance to be covered the the ende of the route,not the distance from the beginning,then it resolve the paradox.

Since it is the distance still left to be covered,it decreases on facing side and increases on reverse side.

Pick C
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by gmatdriller » Sat Aug 07, 2010 1:25 pm
Selango, thanks for the explanations, i got it now.

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by reply2spg » Mon Aug 09, 2010 8:13 am
I will suggest you to go through OG first and then do these questions. Because all your questions are OG alike.
gmatdriller wrote:Selango, thanks for the explanations, i got it now.
Sudhanshu
(have lot of things to learn from all of you)