In correcting this number: "0.39" to 3 d.p and 3 s.f, would it be as follows?

3 d.p --> 0.390

3 s.f --> 0.390

Thanks.

- Jan 4th 2011, 12:48 PMSWEngineerCorrecting to 3 decimal places (3 d.p) and to 3 significant figures (3 s.f)
In correcting this number: "0.39" to 3 d.p and 3 s.f, would it be as follows?

3 d.p --> 0.390

3 s.f --> 0.390

Thanks. - Jan 4th 2011, 12:52 PMrtblue
Yes, you are correct.

For any further questions on significant digits, try this website:

Significant Figures - Jan 4th 2011, 12:54 PMpickslides
- Jan 4th 2011, 12:57 PMrtblue
0.39 can also be expressed as $\displaystyle 3.90*10^{-1}$, in which case there are three significant digits.

- Jan 4th 2011, 12:58 PMSWEngineer
But, even that the last zero can be ommited after the decimal place, we are asked here for 3 s.f, which means there should be three numbers.

For example, what is the solution for this question:

Correct 0.0004298 to 3 s.f? When you solve it you will know what I mean.

Thanks. - Jan 4th 2011, 12:59 PMrtblue
0.0004298 to 3 significant figures would be 0.000430

- Jan 4th 2011, 01:01 PMSWEngineer
- Jan 4th 2011, 03:54 PMHallsofIvy
Yes, because the number of "significant digits" tells you the

**accuracy**of the measurement. 0.39 means that, measured to the nearest hundreth, the number is 0.39- that is that the true value is somewhere between 0.385 and 0.395. 0.390 means that it was measured to**thousandths**place- the true value is between 0.3995 and 0.3905.

Quote:

For example, what is the solution for this question:

Correct 0.0004298 to 3 s.f? When you solve it you will know what I mean.

Thanks.

- Jan 8th 2011, 11:22 PMSWEngineer
Thanks a lot for your replies.