Question

add or subtract the following measurements. be sure each answer you enter contains the correct number of significant digits. 2.800 g - 1.0 g = □ g 19.90 g + 0.670 g = □ g 19.700 g - 1.57 g = □ g

Explanation:

First Calculation: \( 2.800 \, \text{g} - 1.0 \, \text{g} \)

Step1: Perform the subtraction

\( 2.800 - 1.0 = 1.800 \)

Step2: Determine significant figures

When subtracting, the result should have the same number of decimal places as the least precise measurement. \( 2.800 \) has three decimal places, \( 1.0 \) has one decimal place. So we round to one decimal place. \( 1.800 \) rounded to one decimal place is \( 1.8 \).

Step1: Perform the addition

\( 19.90 + 0.670 = 20.570 \)

Step2: Determine significant figures

When adding, the result should have the same number of decimal places as the least precise measurement. \( 19.90 \) has two decimal places, \( 0.670 \) has three decimal places. So we round to two decimal places. \( 20.570 \) rounded to two decimal places is \( 20.57 \).

Step1: Perform the subtraction

\( 19.700 - 1.57 = 18.130 \)

Step2: Determine significant figures

When subtracting, the result should have the same number of decimal places as the least precise measurement. \( 19.700 \) has three decimal places, \( 1.57 \) has two decimal places. So we round to two decimal places. \( 18.130 \) rounded to two decimal places is \( 18.13 \).

Answer:

\( 1.8 \, \text{g} \)

Second Calculation: \( 19.90 \, \text{g} + 0.670 \, \text{g} \)