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I am not a mathematician(IANAM), however I wish I could be.

My question: I often find this at the bottom of pages.

Page generated in 0.00013899803161621

Sometimes, I come across

Page generated in 9.0122222900391E-5

What does that time mean?

I tried searching Wikipedia for E and maths but found the e mathematical constant with a scary looking graph. My guess is E stand for Exponential or something and -5 is the power it is raised to. And the time is a really small number. But that doesn't make sense when compared to the other time in the question is 0.00013899803161621 bigger than 9.0122222900391E-5?

If it means x times $10^{-5}$, then 9.0122222900391E-5 will be 0.000090122222900391 which is smaller than 0.00013899803161621

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    How did it get so many views? It was linked from somewhere else...somewhere with lots of users.2017-07-18

3 Answers 3

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It means $9.0122222900391\times 10^{-5}$. This is known as "scientific notation".

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    so `eN` or `e(N)` always means `10^N` or `10^(N)`??2018-11-18
15

E-5 just means x 10^(-5) i.e. divided by 100000

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    if `-5` is positive, it's multiplication? it's only division when `-5` is a negative like `-5`??2018-11-18
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I have always taken the E or e to mean "exponent of 10." This construction parses in all modern computing languages as an IEEE754 double or single precision number.