00:01
Hello, in this question we are given the rainfall data.
00:05
Okay, so we need to calculate the average rainfall using two methods.
00:10
One is arthematic method and another is thysen polygon method.
00:16
Okay, so in arthematic methods there is the normal mean of the rainfall data from all the rain gauges that lie within the water side.
00:30
Okay, so in our diagram we can clearly see that a, b, e and d lie within the water set.
00:38
A, b, e and d lie within the water set and c and f lie outside of it.
00:46
So, p mean value will be precipitation at a, precipitation at b, precipitation at e and d divided by 4.
00:58
So this would be 2 .2 plus for b it is 3 .22.
01:09
For e it is 2 .49 and for d it is 0 .88.
01:19
That must be divided by 4.
01:22
So this mean value is coming out to be, let me calculate it.
01:31
2 .2 plus 3 .22 plus 2 .49 plus 0 .89 plus 0 .88 divided by.
01:39
So the mean rainfall over here is 2 .1975 inches as per the arthematic method.
01:50
And the second method over here is thysen polygon method...