A line that rises from left to right has a positive slope
We know that the number of users triple each day
Let number of users on day 1 be x
⇒ Users on day 2 =
= 3x
and Users on day 3 =
= 9x
And so on...
% Increase in users from day 1 to day 2 = 
⇒ % Increase in users from day 1 to day 2 = 
⇒ % Increase in users from day 1 to day 2 = 
⇒ % Increase in users from day 1 to day 2 = 200%
Similarly,
% Increase in users from day 2 to day 3 = 
⇒ % Increase in users from day 2 to day 3 = 
⇒ % Increase in users from day 2 to day 3 = 
⇒ % Increase in users from day 2 to day 3 = 200%
Hence, we can see that the percentage increase each day is 200%
For the answer to the question above,
The expected value in percentage format is 0.2 x 15+0.4 x 20 + 0.3 x 30 + 0.1*35 = <u><em>23.5%</em></u>
The answer is <u><em>23.5%
</em></u>
I hope my answer helped you. Have a nice day ahead!
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