Answer:
The percent change will be a 25% decrease
Step-by-step explanation:
In order to find this, we can first call the original positive number a. Now to find how much it would be when we add 50% of that, we can create the following equation.
a + .5a = 1.5a
Now we need to take 50% of that result. To do that, we can multiply by .5.
1.5a * .5 = .75a
Since the end result of the adding and subtracting 50% is .75a, we know that it is just 75% of the original number.