The weight of an object changed by +25.0%. The object's final weight was 2.5 grams. What is the initial weight of the object?

1.25 Wo = 2.5 (grams)

Solve for Wo (the initial weight)

Grams are not usually considered a proper unit for weight, in physics. They should have said mass.

To find the initial weight of the object, we need to reverse the effect of the +25.0% change in weight.

Let's break down the problem step by step:

1. Convert the percentage change to a decimal: +25.0% = 25.0/100 = 0.25.

2. Add 1 to the decimal form of the percentage change to get the multiplier for the final weight: 1 + 0.25 = 1.25.

3. Divide the final weight by the multiplier to get the initial weight: 2.5g ÷ 1.25 = 2g.

Therefore, the initial weight of the object was 2 grams.