Inactive Tutor answered • 06/23/15
Tutor
New to Wyzant
Hi Melani,
The easiest way to determine what measurement is the most precise is to convert them into scientific notation. Then, the most precise measurement is the one that, when written in scientific notation, has the most digits. An example of scientific notation is when you write the number 14 as 1.4x101 (or 128 as 1.28x102, etc).
24.36 --> 2.436x101
18.5 --> 1.85x101
37 --> 3.7x101
50 --> 5x101
So, 24.36 is the most precise measurement.
Inactive Tutor
David,
I made a judgment call based on the trend of the other numbers to say 50 was only one sigfig, but you're right that it could be two. Thankfully, either way it is beaten out by 24.36cm.
Report
06/23/15
Inactive Tutor
50 is considered to have only 1 sigfig while 50. with the decimal expressed denotes 2 sigfigs, so 50 is 5x101 in scientific notation.
Report
06/23/15
Inactive Tutor
Precision involves the closeness of several measurements, so a single measurement does not indicate precision. The stated problem is actually seeking the best "measurement discrimination".
Report
06/23/15
Inactive Tutor
06/23/15