Question

directions: express the results of the following two calculations to the correct number of significant figures and with the correct units. please be sure to highlight and underline your final answer! 12.) 3.21 g + 0.3 g (2 points) 13.) 5.7 cm x 0.2 cm (2 points)

Explanation:

Step1: Perform addition

$3.21\ g+ 0.3\ g=3.51\ g$

Step2: Apply significant - figure rule for addition

When adding, we look at the decimal place. 0.3 has one decimal place. Rounding 3.51 to one decimal place gives 3.5 g.

Step3: Perform multiplication

$5.7\ cm\times0.2\ cm = 1.14\ cm^{2}$

Step4: Apply significant - figure rule for multiplication

5.7 has two significant figures and 0.2 has one significant figure. The result should have one significant figure. Rounding 1.14 to one significant figure gives 1 $cm^{2}$

Answer:

1. 3.5 g
2. 1 $cm^{2}$