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The fourth proportional to 0.12, 0.21 and 8 is-

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Answer:- 1

Explanation:-

Solution:

Let the fourth proportional to 0.12, 0.21 and 8 be x.

\begin{aligned} Then, \\ = 0 .12 : 0 .21 :: 8 : x \\ \Rightarrow 0 .12 x = 0.21 \times 8 \\ \Rightarrow x = \frac{0.21 \times 8}{0.12} \\ = \frac{21 \times 8}{12} \\ = 14. \end{aligned}

$\eqalign{ & {\text{Then,}} \cr & = {\text{0}}{\text{.12}}:{\text{0}}{\text{.21}}::{\text{8}}:x \cr & \Rightarrow {\text{0}}{\text{.12}}x = 0.21 \times 8 \cr & \Rightarrow x = \frac{{0.21 \times 8}}{{0.12}} \cr & \,\,\,\,\,\,\,\,\,\,\,\, = \frac{{21 \times 8}}{{12}} \cr & \,\,\,\,\,\,\,\,\,\,\,\, = 14. \cr}$

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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 fourth proportional to 0.12, 0.21 and 8 be x.

\begin{aligned} Then, \\ = 0 .12 : 0 .21 :: 8 : x \\ \Rightarrow 0 .12 x = 0.21 \times 8 \\ \Rightarrow x = \frac{0.21 \times 8}{0.12} \\ = \frac{21 \times 8}{12} \\ = 14. \end{aligned}

$\eqalign{ & {\text{Then,}} \cr & = {\text{0}}{\text{.12}}:{\text{0}}{\text{.21}}::{\text{8}}:x \cr & \Rightarrow {\text{0}}{\text{.12}}x = 0.21 \times 8 \cr & \Rightarrow x = \frac{{0.21 \times 8}}{{0.12}} \cr & \,\,\,\,\,\,\,\,\,\,\,\, = \frac{{21 \times 8}}{{12}} \cr & \,\,\,\,\,\,\,\,\,\,\,\, = 14. \cr}$ ", "dateCreated": "7/24/2019 10:09:12 AM" } }

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