A Sense of Scale

If the entire course of evolution were compressed into a single year, the earliest bacteria would appear at the end of March, but we wouldn’t see the first human ancestors until 6 a.m. on December 31.
That’s from Why Evolution is True by Jerry Coyne (which I am reading right now).
P.S. The first organism – simple [...]

Go Forth and Multiply

I came across this bizarre yet sophisticated system of multiplication used in Ethiopia before the age of calculators and computers.
In order to multiply any two numbers, all you need to know is how to halve a number and how to double it. Don’t believe it? Check out the video below:

Essentially, this ancient system breaks the multiplication [...]

Math Clock

Just got this wonderful math clock (for my office) in mail today.

Here’s the explanation of clock numerals. My favorite is the numeral for 5 o’clock that involves the golden ratio, which I wrote about few posts ago (here).
[Hat Tip: Udhay]

Numbers Don’t Lie

According to the Benford’s law, the first digits in many real life data follow a particular pattern such that the number 1 will be the most common as the first digit, number 2 will be the next most common, then 3 and so on. For example, one out of three times you will see 1 [...]

Numbers and Nature

This post is about two numbers (sequences) and their occurrences in nature. The first one is the golden ratio: two quantities are in the golden ratio if the ratio between the sum of those quantities and the larger one is the same as the ratio between the larger one and the smaller. The value of [...]

Million vs. Billion

To grasp the difference between a million (1,000,000) and a billion (1,000,000,000), consider the following:

It takes about 11 and a half day for one million seconds to tick.

And it takes almost 32 years (yeah, that’s right) for one billion seconds to tick!

Now think about the US Treasury’s $700 billion financial stabilization fund for a moment.
The [...]

Happy Leap Day!

Tomorrow is 29th February, a leap day in the leap year of 2008.
Refreshing the logic for determination for leap year:

If a year is divisible by 4 but not by 100 –> Leap year

If a year is divisible by 400 –> Leap year

The Gregorian calendar has 365 days in a year. But a solar year has [...]

Once in a Blue Moon

It takes about 27 days for the Moon to circle around the Earth, but due to Earth’s own circular movement around the Sun it takes few more days for the Moon to complete the full circle – so the Moon will be in the exact same location (with respect to Earth) in about 29 days. [...]