#1

Even if you'e not named Robert.

So, im sitting there, just finished my maths homework...i open my Physics stuff..and relaise that i've forgotten how to do significant figures.

help!

the first question is - round 11.85467 to 3 significant figures.

Once i get tht, i'll know what im doing, but a little explanation would be great:P

So, im sitting there, just finished my maths homework...i open my Physics stuff..and relaise that i've forgotten how to do significant figures.

help!

the first question is - round 11.85467 to 3 significant figures.

Once i get tht, i'll know what im doing, but a little explanation would be great:P

#2

google..

^^ i only said that because i forgot myself

^^ i only said that because i forgot myself

#3

11.9. Significant figures means every number.

#4

^^isnt that rounding?

i'd have thought it'd be 11.8? jst guessing.

i'd have thought it'd be 11.8? jst guessing.

#5

Seriously.

#6

11.9

#7

i cant help t, i think the last time i used it was about 3 years ago.

#8

^^isnt that rounding?

i'd have thought it'd be 11.8? jst guessing.

It's 11.9

You have to round to get the right number of sig figs.

#9

^^isnt that rounding?

i'd have thought it'd be 11.8? jst guessing.

Yes it is rounding... to 3 significant figures. You said it yourself - 'round 11.85467 to 3 significant figures'.

#10

11.9. Significant figures means every number.

Unless they are zeros at the start. 0.000345 to 3 s.f. isn't 0.00. You strat from the first not zero number, but after that zeros count...

#11

11.85467

-> 11.8547

-> -> 11.855

-> -> -> 11.86

-> -> -> -> 11.9

-> 11.8547

-> -> 11.855

-> -> -> 11.86

-> -> -> -> 11.9

#12

11.9, you round the .85 bit up to 9

#13

i see...cheers guys

EDIT: so is 50.7835 = 50, or 50.7?

EDIT: so is 50.7835 = 50, or 50.7?

#14

Neither, it's 50.8

#15

i see...cheers guys

EDIT: so is 50.7835 = 50, or 50.7?

50.8 to 3 SF

#16

None. Its 50.8 (presuming it's to 3SF).

#17

i see...cheers guys

EDIT: so is 50.7835 = 50, or 50.7?

no 50.8

#18

i see...cheers guys

EDIT: so is 50.7835 = 50, or 50.7?

we are not doing your homework...50.8

#19

^ 50.8

Round it all up. See my example.

Round it all up. See my example.

#20

oops, its to two...sorry :S

#21

Then 51.

Is that all?

Is that all?

#22

11.85467

-> 11.8547

-> -> 11.855

-> -> -> 11.86

-> -> -> -> 11.9

Is that you showing the steps of how you round off? Because if it is, then it's unbelievably wrong

(The answer is right though)

*Last edited by AllTimeNewbie at Sep 22, 2008,*

#23

Is that you showing the steps of how you round off? Because if it is, then it's unbelievably wrong

(The answer is right though)

Well that's how I was taught in school.

#24

that is all chaps, thanks :

#25

Christing hell that was freaky

I'm called Robert if you couldn't guess

I'm called Robert if you couldn't guess

#26

11.85467

-> 11.8547

-> -> 11.855

-> -> -> 11.86

-> -> -> -> 11.9

That's terribly wrong and whilst the answer is right you can't round up every number or it will cause problems later.

#27

That's terribly wrong and whilst the answer is right you can't round up every number or it will cause problems later.

I always thought you round up every digit from the back onwards to make sure the final number rounds correctly.

Eh, it's not in my exams this year,

#28

I always thought you round up every digit from the back onwards to make sure the final number rounds correctly.

Eh, it's not in my exams this year,

No, 'cause if you do it that way, 13.145 would become 13.2, even though it's actually closer to 13.1

#29

i see...cheers guys

EDIT: so is 50.7835 = 50, or 50.7?

5-9 you round up, 1-4 you round down.

So 50.455 to 3 sig figs would be 50.5 and 50.449 to 3 sig figs would be 50.4.

Haven't done maths in 6 years but I'm pretty sure that's right.

#30

No, 'cause if you do it that way, 13.145 would become 13.2, even though it's actually closer to 13.1

Ah, so it is, thankyou oh masterful one.

#31

Rounding to significant figures:

Just count the numbers along, so if it's 51.2365 to 3 S.F, it's 51.2.

However, if the number is 0.0032154, the answer isn't 0.

You can ignore the zeroes before the digits that "count", so that would be 0.00322.

Just count the numbers along, so if it's 51.2365 to 3 S.F, it's 51.2.

However, if the number is 0.0032154, the answer isn't 0.

You can ignore the zeroes before the digits that "count", so that would be 0.00322.

#32

Hey, can I ask how old you are?

#33

Me?

I'm 22

I'm 22

#34

No, TS.

#35

11.85467

-> 11.8547

-> -> 11.855

-> -> -> 11.86

-> -> -> -> 11.9

This is the best explanation.

#36

This is the best explanation.

Not really, He arrives at the right answer, but his method is incorrect.

#37

My names Robert you SOB

#38

ah well....

Im 15, and we did dig Fig last year, but i forgot it :P

Im 15, and we did dig Fig last year, but i forgot it :P

#39

11.9. Significant figures means every number.

Done and done. Close thread.

#40

oops, its to two...sorry :S

so then its 51.

a significant digit is any number from 1-9

51 contains two significant digits.

50.9, however, contains three because the zero is also significant.