Question

question 1 (1 point)
four students measure the mass of an object, each using a different scale. they record their results as follows: a: 49.06g, b: 49g, c: 50g, d: 49.2g. which student used the most precise scale?
a
b
c
d
question 2 (1 point)
the length and width of a rectangle are 1.125 m and 0.606 m, respectively. you calculate the rectangles perimeter by adding these and multiplying by two. your calculators display reads 3.462. to the correct number of significant figures, this should be written as
3.5 m.
3.46 m.
3.462 m.
3.4620 m.

Explanation:

Question 1

Step1: Understand precision

Precision refers to the number of decimal places.

Step2: Analyze each measurement

• Student A: \(49.06g\) (two decimal places)
• Student B: \(49g\) (no decimal places)
• Student C: \(50g\) (no decimal places)
• Student D: \(49.2g\) (one decimal place)

Question 2

Step1: Calculate the perimeter formula

\(P = 2(l + w)\), where \(l = 1.125m\) and \(w=0.606m\). \(l + w=1.125 + 0.606=1.731m\). Then \(P = 2\times1.731 = 3.462m\)

Step2: Determine significant figures

The rule for addition: the number of decimal places in the result is the same as the least - precise measurement. \(1.125\) has three decimal places and \(0.606\) has three decimal places. When multiplying by \(2\) (an exact number), the number of significant figures is determined by the sum \(l + w\). The sum \(1.731\) has four significant figures. So \(3.462\) should be written as \(3.462m\)

Answer:

Question 1: A. \(49.06g\) (Student A used the most precise scale as it has the most decimal places)
Question 2: \(3.462m\)