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Jenny is 5 feet 8 Inches tall. To find the height h of a light pole, she measured her shadow and the pole's shadow. What is the height of the pole? Give the height as a mixed number (a whole number and a fraction). 5 ft 8 in. 15 S ft 7 ft 9 in. The height of the pole is

Jenny is 5 feet 8 Inches tall. To find the height h of a light pole, she measured-example-1
User Rijul
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1 Answer

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Determine the Jenny height and shadow height in terms of feet.


\begin{gathered} 5\text{ ft 8 in=5 ft +}(8)/(12)\text{ ft} \\ =(17)/(3)\text{ ft} \end{gathered}

For shadow:


\begin{gathered} 7\text{ ft 9 in =7 ft + }(9)/(12)\text{ ft} \\ =(31)/(4)\text{ ft} \end{gathered}

The ratio of height of Jenny to the shadow is equal to the ratio of height of polr to its shadow.

Determine the pole height.


\begin{gathered} (h)/(15.5)=((17)/(3))/((31)/(4)) \\ (2h)/(31)=(68)/(93) \\ h=(34)/(3) \\ =11(1)/(3) \end{gathered}

Thus height of pole is 11 1/3 ft.

Answer:


11(1)/(3)

User Arno Lorentz
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