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# How to round 42.0388 to 3sf (significant figures)? watch

1. This is a really stupid question but how do you round 42.0388 to 3 significant figures?
2. 42.0?
3. (Original post by Philip-flop)
This is a really stupid question but how do you round 42.0388 to 3 significant figures?
42.0
4. Look at the first non-zero figure and count from there
5. (Original post by Slutty Salafi)
Look at the first non-zero figure and count from there
6. (Original post by Student403)
7. Thanks guys. I did think it would be 42.0 but had a stupid moment thinking that rounding to significant numbers meant it couldn't end in zero :P
8. (Original post by Slutty Salafi)
Look at the first non-zero figure and count from there
Great explanation!! Thank you!!
9. (Original post by Philip-flop)
Thanks guys. I did think it would be 42.0 but had a stupid moment thinking that rounding to significant numbers meant it couldn't end in zero :P
They can As long as you're starting from the first (from the left) non-zero digit, you can end in whatever is necessary
10. 42
11. (Original post by Student403)
In that case what does "count" mean in this context?

First non zero figure starting where?

The OP asked how do you round? I don't think they explained that

I'm so bored
12. (Original post by Zinan)
42
?????
13. (Original post by Philip-flop)
This is a really stupid question but how do you round 42.0388 to 3 significant figures?
(Original post by ByronicHero)
42.0?
(Original post by samb1234)
42.0
(Original post by Slutty Salafi)
Look at the first non-zero figure and count from there
(Original post by Student403)

not quite sure this is AS level standard of difficulty.............
14. (Original post by Student403)
?????
I think i misplaced my wallet.
15. (Original post by ByronicHero)
In that case what does "count" mean in this context?

First non zero figure starting where?

The OP asked how do you round? I don't think they explained that

I'm so bored
I can tell
16. (Original post by Student403)
They can As long as you're starting from the first (from the left) non-zero digit, you can end in whatever is necessary
Thank you so much!!! I definitely understand rounding to significant numbers better now!!
17. (Original post by thefatone)
not quite sure this is AS level standard of difficulty.............
It is GCSE, but you might need to know iot for A level

(Original post by Student403)
I can tell
18. It's not a stupid question at all. We all have our strengths and weaknesses. Mine being long subtraction.
19. 40 (3sf)

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