## Writing for Business - A Whatis.com Blog

Nov 7 2012   11:40AM GMT

# Which is larger: a 180 degree change or a 360 degree change?

Profile: Ivy Wigmore

Which is correct?
IT consumerization represents a _______ change in the flow of technology innovation — a complete reversal of the way it used to go.
a. 180 degree
b. 360 degree

Explanation:
People often talk about a 360 degree change in something as if it were a complete reversal but a 360 degree turn actually takes you right back to the original position. Maybe this is why we humans have so much trouble making changes — we keep turning things around 360° and ending up right back where we started. If you want the most change possible, you should aim for 180 degrees.

From Math Is Fun:

## The Full Circle

A Full Circle is 360°

Half a circle is 180°

(called a Straight Angle)

Quarter of a circle  is 90°

(called a Right Angle)

A 90 degree turn takes you a quarter of the way around; a 180 is a complete reversal. Another 90 degrees takes you to 270 and if you go 90 degrees beyond that you’re at 360 degrees, which is back at zero — where you started.

Math is Fun offers this explanation for why we use 360 for the full circle:

Probably because old calendars (such as the Persian Calendar) used 360 days for a year – when they watched the stars they saw them revolve around the North Star one degree per day.

***