we just need to extrapolate the information we have about 25 apples to 100, that is we need to find a number that multiplied by gives us 100, from this original fraction, hence, we have:
2 out of 25 = 2/25
if we multiply and divide a number or fraction by the same number we do not alter its value, so we need to convert the 25 into 100, and that can be done multiplying it by 4, like so:
(2/25)(4/4) = (2*4)/(25*4) = 8/100
So if we have 2 bruised apples out of 25, then we can expect to have 8 bruised apples out of 100
