<PRE><B>Question 1059772</B>
Suppose that the lens on your camera is positioned .85 inches from the film, and that the lens can focus on an object 10 feet away. What is the focal length of the lens?
f= focal length 
p= distance from the lens to object:: 120&quot;
q= distance from lens to the film:: 0.85&quot;
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1/f=1/p+1/q 
1/f = 1/120 + 1/0.85
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1/f = (0.85+120)/(120*0.85)
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f = (120*0.85)/(120.85) = 0.844
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Cheers,
Stan H.
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