From the . or the decimal representation, the left side values increases by the power of 10 which starts from 0.
For example: `100 = 1xx10^2+0xx10^1+0xx10^0`
So the if the first number to the left of the decimal is X, it represents `Xxx10^0` .
If the second number to the left of the decimal is Y, then it represents `Yxx10^1`
If the nth number to the left is P then it would represent `Pxx10^(n-1)`
Similarly if you consider 8,531,980,112.45;
The number 3 is coming at 8th position when we count from the left of decimal symbol.
So it represents `3xx10^((8-1)) = 30000000`
So the answer is 30000000.