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# Percentage error watch

1. I have also used 6 strips in my answer too I don't kNow what went wrong
2. (Original post by coconut64)
Attachment 613532 still not getting the right answer...
The only mistakes I'm noticing is that you're using different s.f. in your approximation, like 1.1054, 1.30 and (2root3)/3, that's not 4.s.f, other than that, it looks fine from what I can see.
3. (Original post by coconut64)
still not getting the right answer...
The approximation from part b) is the value rounded to 4sf.

So in c), to find the percentage error of the approximation you should be using 1.326 in your calculation instead of 1.32564...

If you do that then you'll get 0.687 which you say is the correct answer.
4. (Original post by notnek)
The approximation from part b) is the value rounded to 4sf.

So in c), to find the percentage error of the approximation you should be using 1.326 in your calculation instead of 1.32564...

If you do that then you'll get 0.687 which you say is the correct answer.
Thanks but why would you use the rounded value ? I rounded it as this is what part b wants but when you do the calculation wouldn't you use the actual value though ? Thanks
5. (Original post by coconut64)
Thanks but why would you use the rounded value ? I rounded it as this is what part b wants but when you do the calculation wouldn't you use the actual value though ? Thanks
As I said in my last post, the "approximation" that they're talking about in part c) is the 4sf approximation that you found in b).

You have to use some kind of rounded value anyway since it's an infinite decimal. Using 1.23564... is an approximation up to the amount of decimal places on your calculator. But the approximation that they're talking about is a 4sf approximation.

EDIT : Post "approximation" count = 5
6. (Original post by notnek)
As I said in my last post, the "approximation" that they're talking about in part c) is the 4sf approximation that you found in b).

You have to use some kind of rounded value anyway since it's an infinite decimal. Using 1.23564... is an approximation up to the amount of decimal places on your calculator. But the approximation that they're talking about is a 4sf approximation.

EDIT : Post "approximation" count = 5
Thanks

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