Problems

Approximately how many footsteps do I take in a year? (estimate to the nearest power of \(10\))

What’s \(2\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow\uparrow2\)?

What’s bigger out of \(5^6\) and \(2^{14}\)?

What’s \(3\uparrow\uparrow3\) as a power?

Is \(45^{45}\) bigger or smaller than \(10^{80}\)?

How many times have the people in this room blinked in their lives in total? Find an answer to the nearest power of 10.

What’s bigger out of \(99!\) and \(50^{99}\)?

Let \(x\) be the sum of digits of \(4444^{4444}\). Let \(y\) be the sum of digits of \(x\). What’s the sum of the digits of \(y\)?

Using the fact that \(\log_{10}(3)\approx0.4771\), \(\log_{10}(5)\approx0.698\) and \(\log_{10}(6)\approx0.778\) all correct to three or four decimal places (check), show that \(5\times10^{47}<3^{100}<6\times10^{47}\). How many digits does \(3^{100}\) have, and what’s its first digit?

What is the least \(N\) such that \(\sum_{n=1}^N1/n\ge100\)?