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If an organization collects an average of 20,000 EPS over eight hours of an ongoing incident, that will require sorting and analysis of 576,000,000 data records. Using a 300 byte average size, that amounts to 172.8 gigabytes of data.

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I'm not clear how this 172.8 was calculated. I know 576,000,000 was taken by multiplying 8 hours into seconds. Should i divide the 300 byte average size? Please help.

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closed as off topic by Raphael Nov 9 '12 at 7:59

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This is a question of doing arithmetics, not computer science. It's also too localized. –  Raphael Nov 9 '12 at 7:59

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The calculation is not correct.

You get number of records as $NR=20,000*8*60*60=576,000,000$, where $8*60*60$ is the number of seconds in 8 hours. Then you get the size of the data in bytes as $NR*AVG_{SIZE}=576,000,000*300=172800000000$ bytes. This $172800000000$ bytes are not euqal to $172.8$ gigabytes.

The conversion goes like this:

$1$ kilobyte $=$ $1024$ bytes

$1$ megabyte $=$ $1024$ kilobytes

$1$ gigabyte $=$ $1024$ megabytes

Hence:

$1$ gigabyte $=$ $1024^3$ bytes

For the final conversion to gigabytes you need to divide the number of bytes by $1024^3$. So $172800000000$ bytes$/1024^3=160.932540894$ gigabytes.

Note that if you would be talking about bits, then the conversion would be just to divide by $1000^3$.

Link to wikipedia: see the table in the article.

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