Blake O'Hare .com

Tag: Algebra

Calculating Base 10 Logarithms in Your Head
Posted 6.3 years ago.
Calculating base 10 logarithms in your head on the fly is a lot easier than you may think. It is sim...
Checking a Number for Primeness
Posted 6.4 years ago.
The Pen-and-Paperless version! The following is roughly my thought processes when I try to check to ...
Divisibility Rules for Arbitrary Divisors
Posted 6.4 years ago.
It's rather obvious when a number is divisible by 2 or 5, and some of you probably know how to tell ...
Counting Terminating Zeros in a Factorial
Posted 6.4 years ago.
Ever notice how large factorials always end in a ton of zeros? If not, take a look at 999 Factorial ...
Converting Repeating Decimals Into Fractions
Posted 6.4 years ago.
It's fairly easy to take a fraction and turn it into a repeating decimal by hand. This is simple div...