Question

. What is the result of the following calculation? Record to the correct number of significant figures. 7.94g + 0.0132 g = ?7.9 g 7.95 g7.9532 g7.953 g

Answer 1

We have to do this calculation, according to the rules of significant figures:

For additions or subtractions, we have to express the result with the number of significant figures of the number with the lowest one.

Then, we have to count each number's significant figures:

`\begin{gathered} 7.94\text{ has 3 significant figures. } \\ 0.0132\text{ has also 3 significant figures \lparen the zeros before the decimal point} \\ and\text{ between the decimal point and the other numbers don't count\rparen} \end{gathered}`

Then, the answer has to have 3 significant figures.

`7.94\text{ g}+0.0132\text{ g = 7.9532 g }\approx\text{ 7.95 g \lparen3 significant figures\rparen}`

Then, the answer is the second: 7.95 g