Interpolation?
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Interpolation?
Ok I'm having Saturday morning brain strain!
Could someone put me out of my misery and explain how I interpolate data?
Question: If 2,000ft = 1% fuel penalty what would the fuel penalty be at 2,100ft?
I know the answer is quite straight forward, but I just can't remember how you work this out (and it's not in my maths book) so could someone please help?
Thanks....
Could someone put me out of my misery and explain how I interpolate data?
Question: If 2,000ft = 1% fuel penalty what would the fuel penalty be at 2,100ft?
I know the answer is quite straight forward, but I just can't remember how you work this out (and it's not in my maths book) so could someone please help?
Thanks....
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The way that I read this is:
100 is 1/20th of 2000.
2000ft = 1%. Therefore 100ft = 1/20th of 1% or .05%
Add the percentage for that extra 100ft onto the percentage for 2000ft.
1 + 0.05 = 1.05%
This looks too easy for my liking so it is probably wrong. I will be corrected. What is this for. Is it for those ATPL writtens?
Bill
100 is 1/20th of 2000.
2000ft = 1%. Therefore 100ft = 1/20th of 1% or .05%
Add the percentage for that extra 100ft onto the percentage for 2000ft.
1 + 0.05 = 1.05%
This looks too easy for my liking so it is probably wrong. I will be corrected. What is this for. Is it for those ATPL writtens?
Bill
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JetMouse
My thoughts on this are as follows:
Interpolation is based on two known factors to find a third.
WIRELESS is correct in his working but I am not sure you could call it interpolation. We were given 2000ft and 1% as the only data and asked to find a third value by interpolation. This is not possible with the given data so we must make some assumptions.
I will assume 2000ft and 1% are the LOWER values. I will also assume that the interpolation is linnier so I can assume the UPPER values to be 4000ft and 2%. NOW I have enough data to Interpolate any value between 2000ft and 4000ft.
Given 2100ft I came up with 1.05% which is correct. 2350ft is 1.18% (2dp)
I made a very handy Interpolation formula in excel that I would be happy to email to you...
My thoughts on this are as follows:
Interpolation is based on two known factors to find a third.
WIRELESS is correct in his working but I am not sure you could call it interpolation. We were given 2000ft and 1% as the only data and asked to find a third value by interpolation. This is not possible with the given data so we must make some assumptions.
I will assume 2000ft and 1% are the LOWER values. I will also assume that the interpolation is linnier so I can assume the UPPER values to be 4000ft and 2%. NOW I have enough data to Interpolate any value between 2000ft and 4000ft.
Given 2100ft I came up with 1.05% which is correct. 2350ft is 1.18% (2dp)
I made a very handy Interpolation formula in excel that I would be happy to email to you...
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I guess the easiest way to describe interpolation is to use a data table (provided you have one) to plot a graph and simply read off the required value. I would use the Paramac method but it assumes a linear progression...does the question include any other data?
P.S. I'd like to compliment JetMouse on his use of the "From" field in personal details
P.S. I'd like to compliment JetMouse on his use of the "From" field in personal details
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If the relationship is linear, or near so, then one can use a simple linear proportion, either mentally, or with the prayer wheel CD scales or, if you really can't function without batteries ... your calculator/nav computer. This sort of stuff is covered at PPL theory level in a number of areas ...
If the relationship is not sufficiently linear then there are any number of statistical procedures to interpolate using calculators or simple PC programs.
If the relationship is not sufficiently linear then there are any number of statistical procedures to interpolate using calculators or simple PC programs.