Sig Fig Clarification: 150. vs 150 - Is it Correct?

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This discussion clarifies the concept of significant figures (sig figs) in numerical expressions. The volume of a box measuring 85 m by 92 m by 95 m is calculated as 742,900 m³, but due to the two significant figures in each measurement, it should be reported as 740,000 m³. The number 150 has two significant figures, while 150. has three significant figures because the decimal indicates that the zero is significant. The discussion emphasizes the importance of precision in measurements and reporting.

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just to clarify on sig figs...for example if a question asked what is the volume of a box that is 85 m by 92 m by 95 m, the answer is 742900 m^3 but since each number has 2 sig figs, the answer must be reported as 740,000 m^3?

is that correct?

also, 150 has 2 sig figs but 150. has 3...right?

thanks.
 
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dnt said:
just to clarify on sig figs...for example if a question asked what is the volume of a box that is 85 m by 92 m by 95 m, the answer is 742900 m^3 but since each number has 2 sig figs, the answer must be reported as 740,000 m^3?

is that correct?

also, 150 has 2 sig figs but 150. has 3...right?

thanks.

You've got it.
Actually, it's probably better form to write it as:
7.4 \times 10^{5}
Since that will leave no doubt about whether the zeros are significant.
 
thanks.

regarding the "150 vs 150." - i know how many sig figs it has but can someone explain WHY the decimal at the end makes the 0 significant in 150. compared to only 150?
 
150. is read as 150.0
 
whozum said:
150. is read as 150.0
umm..i don't think so, i think 150.0 has four sig figs, 150. has three, and 150 two.



dnt, the decimal in 150. is just a way of saying that, to the limits of your measuring tool, for example: this stick is exactly 150. metres , not 149, not 151, but 150.
and in the case of 150.0, it would be implied that your measuring tool can measure to the tenth of a metre and for example you could say: this stick measures exactly 150.0 meters, not 150.1 not 150.2, but 150.0, though you know nothing about the second decimal place. it could be 150.01, 150.0[1-9], u don't know, its too precise for ur measuring tool. u get it?
 
It would, of course, be better to write them as 1.5 x 102 if you intend 2 sig figures, 1.50x102 if you intend 3, 1.500x102 if you intend 4.
 
DB said:
umm..i don't think so, i think 150.0 has four sig figs, 150. has three, and 150 two.

i didnt say it IS 150.0, it is understood as 150 and nothing else. exactly 150, it has 3 significant figures.
 
sorry, i missunderstood ur statement
 

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