learning rate in a non doubling sequence

You cannot be asked to calculate the learning rate when it does not involve doubling. That would need the use of anti-logs which are not in the syllabus. You can obviously be asked to calculate any times when you are given the learning rate using the formula provided. I am afraid that you must have misread the question, because even if it had involved doubling and you had been given the time for the first unit and for (say) the 8th unit you would not be able to calculate the learning rate - you need the average rate per unit and not the time for the individual units.

Hi John, I managed to get the question from previous forums and it said first 10units take 120hour time and from 10-30units it further take another 150 hours time ,so what’s the learning rate? This was the same question I had. As always your help will be much appreciated

This is not what you typed out originally because it does not give the time for the first unit or for the 30 unit, and it does involve doubling. You have still not typed the question correct because it actually said that the time for the next 30 units was 150 hours. They are making in batches of 10 units. The time for the first batch is 120 hours. They then make another 3 batches which take 150 hours and gives a total of 4 batches. The average time per batch when they make 4 batches is (120 + 150) / 4 = 67.5 hours. Making 4 batches means doubling twice, so the learning rate = sq root of (67.5/120) = 0.82 (or 82%) I suggest that you watch my free lectures on learning curves.