Answer:
If you want to find the percentages, you must use the equation:
P = ((total tries in where the event is true)/total tries)*100%
(if you only want the decimal form, you can not multiply it by 100% and you will get a number between 0 and 1)
ok, for placebo we have 30 + 8 = 38 tries.
the frequency where the player block the goal is: p1 = (30/38)*100% = 78.9%
the frequency in where the player don't block the goal is:
p2 = (8/38)*100% = 21%
For the luck potion we have a total of:
23 + 5 = 28 tries.
The frequency where the player did block the goal is:
p1 = (23/28)*100% = 82.1%
then the frequency where the player did not block the goal is:
p2 = (5/23)*100% = 17.9%
So we can see that, in percentage, the luck potion is more efficient.