To get the volume of an object, one of the oldest techniques is to fill a container with water of which we know the volume (in this case 85mL), and drop the object in. The water will rise and show a new volume (225mL). If we subtract the old volume (85) from the new volume (225), we will get the volume of the object (225 - 85 = 140).
It will take 6 years for that to happen.
You can find this by setting Nichole's age as x and Sophie's age as x + 28 since she will always be 28 years older.
Now we are looking for a time that Sophie's age is equal to 2 less than 6 times Nichole's age. So we can set up the below equation.
6(x) - 2 = x + 28
6x - 2 = x + 28
5x - 2 = 28
5x = 30
x = 6
This let's us know that it needs to be when Nichole is 6, which is 6 years in the future.
