Here are some cool calculator tricks you can use to find someone's phone number, guess their age and astound them with your math wizardry. If you have any tricks up your own sleeve, please share ...

Lieber says to do this a few times, then he guesses the final number you've landed on. Cool, right? In the video, Lieber says the math behind the trick is part of an idea called the Kruskal count ...

Instead of having one number for your home phone, another for your office, and another for your mobile, Voice gives you a single phone number for everything. When someone calls me, the service ...