Percent of change 25 points to 50 points

Percent change
first find change
then find as a percent out of original

percent mean parts out of 100 so x%=x/100

find change first

25 to 50 is a change of 25

now we do
change/original=x%
change/original=x/100
25/25=x/100
1=x/100
x=100

answer is 100% change

It is blindness and randomization