Extrapolation to reach certain value

I have a set of points, 4 values as follows.

matrix_snr = [2.29e5 1.46e5 1.68e4 2.51e5];
avg_snr = mean(matrix_snr);

Now, this comes to 1.61e5

This is the value from 4 transistors. So how do I extrapolate to find out the number of transistors required to reach an avg_snr value of ~0.5? What mathematical and (MATLAB) approach should I use for this?

Thanks! Please assist.

Please read the below comment for further clarification of this question. Thanks!

[Adam]

You want to extrapolate 4 numbers of the order of 1e5 such that the average of these newly extrapolated numbers will be 0.5?!

[Kash022]

Did you read the question carefully? I'll rephrase it for easier understanding. When I have 4 transistors, I reach an SNR value of 1.6e5 How many transistors would I require to reach an SNR value of 0.5 assuming extrapolation and an exponential distribution relationship between the number of transistors and the SNR?

[Jan]

The question is not clear. If you create the mean over 4 values, there is no way to "extrapolate" the number of elements to get a wanted different mean value. Even reading the question and comment carefully does not make it mathematically meaningful.

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