Solution:
Let x litres of water is required to be added.
Then, total mixture = ( x + 1125) litres
It is evident that the amount of acid contained in the resulting mixture is 45% of 1125 litres.
This resulting mixture will contain more than 25% but less than 30% acid content.
∴30% of (1125 + x ) > 45% of 1125
And, 25% of (1125 + x ) < 45% of 1125
30 % of (1125 + x ) > 45% of 1125

25% of (1125 + x ) < 45% of 1125

∴562.5 < x < 900
Thus, the required number of litres of water that is to be added will have to be more than 562.5 but less than 900.