A flagstaff 17.5 m high casts a shadow of length 40.25 m. The height of the building, which casts a shadow of length 28.75 m under similar conditions will be:

110 m
212.5 m
317.5 m
421.25 m

Answer:- 1

Explanation:-

Solution:

Let the height of the building x metres.
Less lengthy shadow, Less in the height (Direct Proportion)

\begin{aligned} ∴ 40.25 : 28.75 :: 17.5 : x \Leftrightarrow 40.25 \times x = 28.75 \times 17.5 \\ \Rightarrow x = \frac{28.75 \times 17.5}{40.25} \\ \Rightarrow x = 12.5 \end{aligned}

$\eqalign{ & \therefore 40.25:28.75::17.5:x\,\,\, \Leftrightarrow \,\,\,40.25 \times x = 28.75 \times 17.5 \cr & \Rightarrow x = \frac{{28.75 \times 17.5}}{{40.25}} \cr & \Rightarrow x = 12.5 \cr}$

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", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" } }, "suggestedAnswer": { "@type": "Answer", "text": "

Solution:

Let the height of the building x metres.
Less lengthy shadow, Less in the height (Direct Proportion)

\begin{aligned} ∴ 40.25 : 28.75 :: 17.5 : x \Leftrightarrow 40.25 \times x = 28.75 \times 17.5 \\ \Rightarrow x = \frac{28.75 \times 17.5}{40.25} \\ \Rightarrow x = 12.5 \end{aligned}

$\eqalign{ & \therefore 40.25:28.75::17.5:x\,\,\, \Leftrightarrow \,\,\,40.25 \times x = 28.75 \times 17.5 \cr & \Rightarrow x = \frac{{28.75 \times 17.5}}{{40.25}} \cr & \Rightarrow x = 12.5 \cr}$ ", "dateCreated": "7/24/2019 10:09:12 AM" } }