From a calculus instructor from Penn State in 1946

“A man six feet tall stands on a curb, facing a light suspended fifteen feet above the middle of a street thirty feet wide. He begins to walk along the curb at five m.p.h. After he has been walking for ten seconds, at what rate is the length of his shadow increasing?

      —a problem given by my calculus instructor, Penn State, 1946

Did not note who "why" was.

#Calculus #RelatedRates #PennState

Easy Math Editor

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`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
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Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$