# three significant numbers

• Oct 18th 2009, 05:16 AM
datboiantonio
three significant numbers
Can someone tell me the three significant numbers for these below:

I have a 100 of these to do, can someone start me of so that i can get an idea of how to do them. Thanks

1) 34.33333
2) 0.031968
3) 0.268632
4) 0.464704
5) 0.731368
6) 0.266664
7) 0.430167
8) 0.469273
9) 0.581395
10) 0.406779

If you need to round your answer, please give at least 3 significant figures after the decimal point and any initial zeros. E.g. 3.000346.
• Oct 18th 2009, 06:23 AM
datboiantonio
tell me if i got these right please:

1) 34.33333 - 34.333
2) 0.031968 - 0.0319
3) 0.268632 - 0.268
4) 0.464704 - 0.464
5) 0.731368 - 0.731
6) 0.266664 - 0.266
7) 0.430167 - 0.430
8) 0.469273 - 0.469
9) 0.581395 - 0.581
10) 0.406779 - 0.406
• Oct 18th 2009, 08:23 AM
Quote:

Originally Posted by datboiantonio
Can someone tell me the three significant numbers for these below:

I have a 100 of these to do, can someone start me of so that i can get an idea of how to do them. Thanks

1) 34.33333 34.3
2) 0.031968 0.0320
3) 0.268632 0.269
4) 0.464704 0.465
5) 0.731368 0.731
6) 0.266664 0.267
7) 0.430167 0.430
8) 0.469273 0.469
9) 0.581395 0.581
10) 0.406779 0.407

HI

see quote .
• Oct 18th 2009, 01:52 PM
HallsofIvy
The best thing to do is to write the numbers in scientific notation- that's where "significant figures" is most useful.

In scientific notation, 34.33333 is $\displaystyle 3.433333 \times 10^1$. Now round off to the second decimal place.

In scientific notation, 0.031968 is $\displaystyle 3.1968 \times 10^{-2}$. Now round of to thesecond decimal place.
• Oct 18th 2009, 05:04 PM
Guess992
Quote:

Originally Posted by datboiantonio
Can someone tell me the three significant numbers for these below:

I have a 100 of these to do, can someone start me of so that i can get an idea of how to do them. Thanks

1) 34.33333
2) 0.031968
3) 0.268632
4) 0.464704
5) 0.731368
6) 0.266664
7) 0.430167
8) 0.469273
9) 0.581395
10) 0.406779

Basically, significant figures refer to the first n digits starting from the first non-zero.
The first post gave you 3 significant figures for those ten. Just note the first 3, they will cover most scenario's.