#### mathdad

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What is the set for this problem? I am lost.

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What is the set for this problem? I am lost.

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How many miles will an object go in 365 days at a speed of 186,000 miles per second? Find the number of hours in 365 days, and the number of seconds in an hour, and multiply. You may want to look up information about unit conversions, particularly the "unit factor" method (which goes by many names).

Now please show

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How many miles will an object go in 365 days at a speed of 186,000 miles per second? Find the number of hours in 365 days, and the number of seconds in an hour, and multiply. You may want to look up information about unit conversions, particularly the "unit factor" method (which goes by many names).

Now please showwhereyou are lost. Or at least describe what you see from your location, if you don't know where you are.

How many miles will an object go in 365 days at a speed of 186,000 miles per second? Find the number of hours in 365 days, and the number of seconds in an hour, and multiply.

Solution:

One day = 24 hours

365 days = 365(24) = 8,760 hours

****************************

1 minute = 60 seconds

1 hour = 60(60) = 3600 seconds

*****************************

Seconds in one year =

8760(3600) = 31,536,000

Do I now multiply

31,536,000 by 186,000 and then convert to scientific notation?

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\(\displaystyle \frac{365\text{ days}}{1}\cdot\frac{24\text{ hours}}{1\text{ day}}\cdot\frac{3600\text{ sec}}{1\text{ hour}}\cdot\frac{186,000\text{ miles}}{1\text{ sec}}\)

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Great. Can you answer the question in full? I want use it as reference to solve others just like it.

\(\displaystyle \frac{365\text{ days}}{1}\cdot\frac{24\text{ hours}}{1\text{ day}}\cdot\frac{3600\text{ sec}}{1\text{ hour}}\cdot\frac{186,000\text{ miles}}{1\text{ sec}}\)

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Yes. I will finish on paper.He just gave you 90% of the problem. Surely you can finish the rest?

-Dan

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Note: I simply switched from d = rt to

d = vt.

t = 365 days x 24hrs/day x 60 min/h x 60 s/min = 31,536,000 seconds

v = 186,000 miles per seconds

d = vt = (31,536,000 s)(186,000 mps) = 5.865696 x 10^12 miles

I say there are 5.865696 x 10^12 miles in one light year.

Two light years:

2 light years x 5.865696 x 10^12/ light years = 1.1731392 x 10^13 miles.

Correct?

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If the context were one in which significant digits were taken into account, you would want to round to 5.87 * 10^12 miles and 1.17 * 10^13 miles, because 365 and 186,000 are round numbers (3 significant digits each).

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Very cool. Another one for the files.

If the context were one in which significant digits were taken into account, you would want to round to 5.87 * 10^12 miles and 1.17 * 10^13 miles, because 365 and 186,000 are round numbers (3 significant digits each).

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