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How many miles is the universe across?

Answer 1

Hailey Alvarez

The observable universe is approximately #5.4xx10^23# miles in diameter.

In one second, light travels about #186000# miles (in vacuum).

There are #86400# seconds in each days, so in one day light will travel:

#86400 * 186000 ~~ 1.6xx10^10# miles

One year is approximately #365# days, so in one year light will travel:

#365*1.6xx10^10 ~~ 5.8xx10^12# miles

The observable universe is approximately #93# billion light years across, so:

#9.3xx10^10 xx 5.8xx10^12 ~~ 5.4xx10^23# miles

That's #540,000,000,000,000,000,000,000# miles

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Answer 2

Levi Alexander

The observable universe is estimated to be about 93 billion light-years in diameter. This corresponds to roughly 546 sextillion miles.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.