## 09 December 2010

### Fwd: Mathematical study of mobile plan: 1 paisa per second is better or 50 paisa per minute

On my mobile i am applying a tariff vouchers.
I was having 2 options.

1) 50 paisa per second
2) 1 paisa per second

I did some mathamatical calculation

I wrote a small script to generate a data set.

A=50
B=0
TotalDiff=0

for a in seq 1 60
do
for i in seq 1 60
do
let B+=1
let counter+=1
let TotalDiff=$((TotalDiff +$(($B-$A))))
echo $B$A $B$TotalDiff
done
let A+=50

done

This will generate output like

1 50 1 -49
2 50 2 -97
3 50 3 -144
4 50 4 -190
5 50 5 -235
6 50 6 -279
7 50 7 -322
8 50 8 -364
9 50 9 -405
10 50 10 -445
11 50 11 -484
12 50 12 -522
13 50 13 -559

First column is number of second, second column shows amount deducted using first plan, third show amount deducted using second plan (1 paisa per second) , last column is accumulated difference.

For example if you make 3 call, 1 second, 2 second, and 3 second each -
then with first plan, total 150 paisa will be deducted using first plan, second plan will deduct 1+2+3= 6 paisa. Total difference will be , 144 paisa.
So third line show
3 50 3 -144

If you do not call more then 3 second , then using probability theory, you will loose 144/3=  48 paisa per call

but we always call more then this , we usually altleast 10 second and we can call upto more then a hour. I this script generate data set for 1 hour.

I even plotted also..

See image attached

Result shows that If you talk more then 250 second (4 minute 10 second ) then 50 paisa per second will give best result. example, talking one hour (3600 second) will cost only 30 Rupee while 1 paisa will cost you 36 Rupee.

So to all loveboys and girls, i recommend 50 paisa per minute plan

Result shows that if you always talk less then 50 second then 1 paisa per second plan is better.. Ex talking on 10 second will cost you 10 paisa while first plan cost you 10 paisa only

I used probability and found that is 296 second is the crossover second. This is the point from where 50 paisa per minute will give best result. If you never talk more then 296 second "ever" then 1 paisa per second is for you... If you happen to call more then 296 second (appx 5 minute) ever, then 50 paisa per minute is best suitable for you.