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# No. of digits in this number...

## Question

ok, this might be a sitter (or a lifetime effort ) to few:

what is the number of digits in the number

345893456 ^ 345893456 (read as the number raised to itself)

oh yeah, feel free to use ur calculators, super-computers, grids, etc..

## Recommended Posts

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The 50-50-90 rule: Anytime you have a 50-50 chance of getting something right, there's a 90% probability you'll get it wrong

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There's hardly any activity out here! C'mon ppl give it a shot, its not that difficult as it looks...

The 50-50-90 rule: Anytime you have a 50-50 chance of getting something right, there's a 90% probability you'll get it wrong

& yes, i was given this problem recently and was given ten min's to figure it out, thankfully it struck in the 1st min...

Number of digits # 10 ^ 2953564278

Now, here's the tough / easy part given the answer: Explain the reasoning

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It took me a little while, but once I got it I see how someone else could get it much quicker than I did. I would have been pushing the 10 minute time limit.

345893456 * log(345893456)

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It took me a little while, but once I got it I see how someone else could get it much quicker than I did. I would have been pushing the 10 minute time limit.

345893456 * log(345893456)

Bingo!!

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i dont understand... using Log on the second number changes the equation, doesnt it?

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i dont understand... using Log on the second number changes the equation, doesnt it?

Of course it does, hence the 10 ^ ____ in the answer!

y = x^x (read raised to)

log y = x * log x (log to the base 10)

Now go back to logarithmic basics and think!

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