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Is 300 1 significant figure???? My teacher and everyone else say it’s 3

I’m so so confused. I was taught that numbers like 300 are 1 significant figure and things like 300.0 have 4 significant figure. And even google says 300 has one sig fig. Help me out please!!!

If your teacher is a 'qualified maths teacher' and tells you that, report them right away. I really hope they don't teach up to GCSE let alone A levels.

Or maybe they just had a very, very bad day?

Reply 3

Sinnoh

Original post by ArtmisKco

I’m so so confused. I was taught that numbers like 300 are 1 significant figure and things like 300.0 have 4 significant figure. And even google says 300 has one sig fig. Help me out please!!!

it's ambiguous - 295 to 304 can all be written as 300 to 2 s.f., and 299.5 to 300.4 can also be written as 300 to 3s.f.

Reply 4

username4347578

I hope you’re right😭 my alevel chemistry teacher said that for a question and the rest of the class agreed whilst I was confused

Reply 5

username4950464

yeah, it’s 1sf i’m pretty sure. because if you round 276 to 1sf it’d be 300 as you round the 7 upwards

Reply 6

ghostwalker

Original post by ArtmisKco

I hope you’re right😭 my alevel chemistry teacher said that for a question and the rest of the class agreed whilst I was confused

Since you mention chemistry, I have to ask what was the actual question and context.

Edit: E.g. If you were weighing a substance to the nearest gramme, then 300 would be to 3 sig.fig.

(edited 4 years ago)

Reply 7

Notnek

It's an ambiguous case. But who really cares if it's 3 or 1? 300 is an exact number that doesn't need to be rounded so is this question even valid?

Original post by Justvisited

If your teacher is a 'qualified maths teacher' and tells you that, report them right away. I really hope they don't teach up to GCSE let alone A levels.

Or maybe they just had a very, very bad day?

I disagree.

Reply 8

Notnek

Original post by ArtmisKco

I hope you’re right😭 my alevel chemistry teacher said that for a question and the rest of the class agreed whilst I was confused

What was the question?

Reply 9

MarkFromWales

In isolation, if I was asked the accuracy of 300, I'd say 1 significant figure, but in a context it can be two or three significant figures. For example, if you gave me a list of measurements as follows:
180 cm, 22 cm, 300 cm, 1.9 cm, 1600 cm, 310 cm, 9.9 cm
then I'd say that you were measuring to an accuracy of 2 significant figures, so in this context the 300 is accurate to 2 significant figures. Sometimes maths is a bit weird! Just to repeat, normally, with no context, 300 has 1 significant figure.

Reply 10

username4347578

It was. Chemistry question. The question. Said write your answers to an appropriate degree of significant figures and my teacher taught us that since it doesn’t say exactly to what significant figures you have to find one of the numbers used in the question with the lowest significant figures. I say it’s one sit fig due to 300 but they said it had 3 significant figures and it’s

the lowest significant figures. Help please

Reply 11

ghostwalker

Original post by ArtmisKco

Within the context of the question, 300K is to 3 sig.fig. If you look at a thermometer and read the temperature it's invariably at least accurate to the nearest degree. And that's a standard thermometer, let alone a fancy one for the experiment.

(edited 4 years ago)

Reply 12

username4347578

Original post by ghostwalker

Within the context of the question, 300K is to 3 sig.fig. If you look at a thermometer and read the temperature it's invariably at least accurate to the nearest degree.

But that’s really confusing. Should I just know this for chemistry? 95000 was also used in the question so would that then be to 5 significant figures?

Reply 13

nzy

Original post by ArtmisKco

But that’s really confusing. Should I just know this for chemistry? 95000 was also used in the question so would that then be to 5 significant figures?

All the other data in the question is given to 3sf, so I think it's safer to assume that 95,000 is also to 3sf.

Reply 14

ghostwalker

Original post by ArtmisKco

But that’s really confusing. Should I just know this for chemistry? 95000 was also used in the question so would that then be to 5 significant figures?

Yes, you should know it for chemistry.

The 95000 is the iffy one. Depends on the accuracy of the measuring device. And for that I don't know what the degree of accuracy is.

Reply 15

username4347578

Original post by nzy

All the other data in the question is given to 3sf, so I think it's safer to assume that 95,000 is also to 3sf.

Ah ok all right. So in the future I’ll need to be careful of the other numbers used to see to what significant figures they are right?

Reply 16

nzy

Original post by ArtmisKco

Ah ok all right. So in the future I’ll need to be careful of the other numbers used to see to what significant figures they are right?

Yup. That's generally how you have to do it I'm afraid, and by the looks of it that's really what the question is trying to catch you out on.

Reply 17

username4347578

Original post by nzy

Yup. That's generally how you have to do it I'm afraid, and by the looks of it that's really what the question is trying to catch you out on.

Ah thank you very much :smile:

Reply 18

h3110

- First reply to OP tells him to report the teacher and says he isn't fit to teach maths
- After asking some basic information it turns out the teacher was actually correct
very nice tsr