Adding the correct number of days considering a starting date

I went through a lot of forums and was not able to find the solution for my problem.
Problem: I have a start date, let's say 23-08-2016. If I want to add 3 months, I could just use edate(A1,B1). However, the number of months depends on a success rate, let's say 25%. The problem is that edate(A1;B1*C1) will assume that the number of months is 0,75 (3 months * 25%) and will round to 0 months.

An extra difficulty is that if my start date is February and I would like to add 0,75 months (or other value), then the formula should now that February has 28 (or 29) days, April 30 days, May 31 days and so on.

A1: 23-08-2016 | B1: 3 | C1: 25%

I tried datedif, offset, and others, and was not able to achieve any good results, because the end date varies according to the month of the start date.

Any help would be much appreciated.

Thank you

Given that there is no finite number of days we can assign to represent 1 month, then trying to say 75% of 1 month will naturally be inherent with inaccuracies.

I think the closest we can get to a finite number representing 1 month is
(365.25*4)/48 = 30.4375

So if we multiply the number of months to add by 30.4375, then multiply that result by 75%
That's as close to accurate as you're going to get. I think.

So if
A1 = Start Date
B1 = Number of Months
C1 = Percentage

And assuming we would want to round the result of that calculation (to add an even number of days, instead of like 20.7432)
Try

=A1+ROUND(B1*30.4375*C1,0)

@AliGW

Why not just
EDATE(F2,G2)-F2

EDATE(F2,G2)-F2
Gives the same result as
DATEDIF(F2,EDATE(F2,G2),"d")

So your formula
=F2+(DATEDIF(F2,EDATE(F2,G2),"d")*H2)
Replace the DateDif with just the edate-F2
=F2+(EDATE(F2,G2)-F2*H2)

But there will be the order of operations problem, so that needs to be
=F2+((EDATE(F2,G2)-F2)*H2)

AliGW and all,
Thank you very much, your solution proved to be spectacular and simple.
Much appreciated.
Joćo