I have the next film named Blade Runner and it has two version (director cut and theatrical cut) and I rate the director cut with a 7 and the theatrical cut with a 8, so the average would be:
(7 + 8) / 2 = 7.5
I have another average of all films (the 7 and 8 scores are of blade runner, the 9 and 10 scores are from other films) as below:
(7 + 8 + 9 + 10) / 4 = 8.5
Knowing ONLY the total of scores (2) and the average (7.5) (without the scores) of Blade Runner, I want remove it of the average of films (Also, knowing only its total scores (4) and average (8.5) of all films). Is Possible do it? Or I need to know the scores of all films to calculate the new average?
Best Answer
Yes, I think it's possible based on my understanding of your question: $$ \text{New average} = \frac{\underbrace{8.5 \times 4}_{\text{sum of all ratings}} - \underbrace{7.5 \times 2}_{\text{sum of Blade runner ratings}}}{\underbrace{4-2}_{\text{number of films without Blade Runner}}} = 9.5 $$