So if we set x as the variable for the previous box, then we can set up a simple algebraic equation....
If the old box is 100% of itself [100/100 = 1], then it is 1*x, which is simply written as x.
The new box is 25% more, meaning that it is 100% + 25% of x [100/100 + 25/100 = 125/100 = 1.25], and this is written as 1.25x.
If the new box holds 2kg, then we have sufficient information to solve for x.
1.25x = 2
x = 2/1.25
x = 1.6
And there you have it! The old box could hold 1.6 kilograms.
