Help With a Word Problem

[mba2015]

If you are looking at the horizon, you are on a 12,000 foot mountain top, how many miles are you from the horizon. D = 1.2 sq H.
H= 12,000, so I would take the square of 12,000 which is (109.54) and then multiply 109.54*1.2 which is 131.448
my answer is 131.448 miles. Did I do this problem the right way? Any help would be appreciated. Thank you.

 

[Ishuda]

If you are looking at the horizon, you are on a 12,000 foot mountain top, how many miles are you from the horizon. D = 1.2 sq H.
H= 12,000, so I would take the square of 12,000 which is (109.54) and then multiply 109.54*1.2 which is 131.448
my answer is 131.448 miles. Did I do this problem the right way? Any help would be appreciated. Thank you.

Yes, you did do it the right way. Congrats.

But, just to be more formal, actually Yes and No When giving answers, values should be given for the same number of figures not the same number of decimal places. You gave the square root of 12,000 to 5 significant figures (5 numbers), so when you use that number (109.54), you should round off your answer to 5 significant figures (5 numbers), that is 131.45 miles.

Using this problem as an example and using a spread sheet program good to at least ten significant figures, the actual value to 6 significant figures is 131.453 which rounds to 131.45 miles.

EDIT: And, of course, that is assuming the 1.2 is 1.2 to at least 6 or so significant figures.