multiplying and significant figs
posted by carl on .
Multipy and keep only the correct number of significant figures.
101.6 * 3

304.8 the sig fig does not go down on this problem.

Thank you so much! What about 1300 * 2.16? I know that probably also looks very simple but sig figs are confusing me, such a new concept.

That is 2808, but let me show you how to easily calculate this out. For an example, 1507*1.93. If you plug this into a calculator you get the answer of 2908.51. Significant figures are just simplified numbers that engineers use. Since there is no machine that can go to such exacts, most teachers would tell you to NOT round the numbers, but simply to cut the number short after the tenth place. The answer to my sample would be 2908.5. Say that you get an answer like 2502.27. Think about the problem for a second. Some would quickly answer 2502.3, but look again. Significant figures just hate to be over the number that they equaled to be, so the actual answer would be 2502.2. Try a few more problems and show me your work. It's ok if you don't get the sig figs right away.

Hmm, does your teacher want a specific decimal place? If so, you just tell the numbers as they calculate out to that decimal place (ie 0.284926493 if asked for ten thousandth place would just be 0.2849).