this is a long shot... ln(x) = ?

hxc87x

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Jan 16, 2008
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here's what i have:
ln(x) = -0.02288669

(x) is supposed to be +- 0.9715

i have no idea how to do the last step, which is to convert that ln thingie to get my (x) which would be my learning curve. i also dont have my text book on me so i cant even check that...

anyone have any idea on how to do this?
 

Pitbull

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Apr 8, 2006
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here's what i have:
ln(x) = -0.02288669

(x) is supposed to be +- 0.9715

i have no idea how to do the last step, which is to convert that ln thingie to get my (x) which would be my learning curve. i also dont have my text book on me so i cant even check that...

anyone have any idea on how to do this?
Pls post the full question, this is incomplete
 

hxc87x

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Jan 16, 2008
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ok...

A worker currently completes 20 units per hour. Took him 75 hours to complete the first 1000 units in a process in which the time of the first unit was halved. Learning curve applies for first 1 000 units.
Calculate the learning curve.

Ln Y = Ln a + (Ln LC/Ln 2) . Ln X

Y(x) = aX^b

Y(x)= cumulative average time per unit
a= time it took to complete first unit
X= range of units completed
b= LOG(learning curve)/LOG2

here's what i've done:

60min/20units = 3min/unit
1st unit = 6min
average = 75x60/1000 = 4.5min/unit

Ln Y = Ln a + (Ln LC/Ln 2) . Ln X
Ln4.5 = Ln6 + (Ln LC/Ln2) x Ln1000

simplified, you get:
Ln LC = -0.0288669

now i just need to finish up...

i think that e thing might be it... will try quick
 

hxc87x

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yeah, the e thing worked.
e^-0.0288669 = 0.971545699

thanks guys.
 

Ady

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Aug 17, 2007
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Still don't know how i passed most of my subjects with equations in.
 

hxc87x

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it's a pain in the ass.
no idea really, has something to do with exponents and logarithms. or something.
also, it's a button on my calculator.
 
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