Wednesday, 9 December 2015

Even-Odd car formula of Delhi Government

The new initiative Even-Odd car formula of Delhi government to control traffic and

air pollution is making rounds in the news now-a-days. I just thought of simple

math behind this.

We can easily conclude that this initiative will bring down car traffic by 50%.

But how? This small write up is to bring out simple logic behind this conclusion.

The formula states that all even number registered cars are allowed to commute on

roads on even numbered days (2nd, 4th, 6th etc… of a month) and odd numbered cars

catch up on odd numbered days. Ideally, this should mean - on an odd numbered day,

all odd numbered cars commute on roads and the next day, which is eventually an

even numbered day, all even numbered cars commute on roads.

What does it mean?

If I consider any two consecutive days, “all odd” plus “all even” result in 

distribution of all cars in any two consecutive days. So it brings the day-average 

traffic to half proportion.