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# Upper & Lower Bounds Exam Question Help watch

1. I'm really struggling with finding bounds for decimal places. I also don't understand what it means by "substitute degree of accuracy". The question is:

24e = (square root of s) divided by t

s = 3.47 correct to 2dp
t = 8.132 correct to 3dp

"Work out e to substitute degree of accuracy. Show all working out and give a reason"

If anyone could help I would be extremely grateful!
2. typo?

migh the question not mean "scientific"...?
3. (Original post by Hasufel)
typo?

migh the question not mean "scientific"...?
Yes, I think so.
4. (Original post by steph_11011)
I'm really struggling with finding bounds for decimal places. I also don't understand what it means by "substitute degree of accuracy". The question is:

24e = (square root of s) divided by t

s = 3.47 correct to 2dp
t = 8.132 correct to 3dp

"Work out e to substitute degree of accuracy. Show all working out and give a reason"

If anyone could help I would be extremely grateful!
First of all, work out the upper bound of the question and the lower bound of the question. Then work out the middle of them both to get an suitable degree of accuracy.

To work out the upper bound use the formula, Upper Bound / Lower Bound for this type of equation.

To work out the lower bound use the formula, Lower Bound / Upper Bound for this type of equation.

So, 24e = (square root of s) / t

Not going to give you the answer.
But here is how it works.

For the Lower Bound:
24e = (Square root of s) - Lower Bound / T (Upper Bound)
Then to find e = Divide that ^ answer by 24.

Do the same for Upper Bound, but replace the formulas.

Then work out the average, and that should be the answer !
5. (Original post by Hasufel)
typo?

migh the question not mean "scientific"...?
He probably meant suitable degree of accuracy.
6. (Original post by Chittesh14)
He probably meant suitable degree of accuracy.
Ahhh! -
7. (Original post by Chittesh14)
First of all, work out the upper bound of the question and the lower bound of the question. Then work out the middle of them both to get an suitable degree of accuracy.

To work out the upper bound use the formula, Upper Bound / Lower Bound for this type of equation.

To work out the lower bound use the formula, Lower Bound / Upper Bound for this type of equation.

So, 24e = (square root of s) / t

Not going to give you the answer.
But here is how it works.

For the Lower Bound:
24e = (Square root of s) - Lower Bound / T (Upper Bound)
Then to find e = Divide that ^ answer by 24.

Do the same for Upper Bound, but replace the formulas.

Then work out the average, and that should be the answer !
How many decimal places should the answer be accurate up to?
8. (Original post by Darshan98)
How many decimal places should the answer be accurate up to?
You can make it either 3 significant figures or 4 significant figures.
But in this question, as the number e will be so low and will have at least 1 or 2 leading zeros - I would recommend 3 decimal places or 4 decimal places.
9. i have got this question:
w= square root of (x/y)
x=5.43 correct to 2 decimal places
y=4.514 correct to 3 decimal places
calculate w to a suitable degree of accuracy
10. (Original post by Darshan98)
i have got this question:
w= square root of (x/y)
x=5.43 correct to 2 decimal places
y=4.514 correct to 3 decimal places
calculate w to a suitable degree of accuracy
I would say 3 significant figures.

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