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Complite the following table given that x varies directly as y .  x 2.5 ... ... 15 y 5 8 12 ... - Mathematics

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Question

Complite the following table given that x varies directly as y

x 2.5 ... ... 15
y 5 8 12 ...
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Solution

\[\text{ Here, x and y vary directly }  . \]
\[ \therefore x = ky\]
\[x = 2 . 5 \text{ and  } my = 5\]
\[i . e . , 2 . 5 = k \times 5\]
\[ \Rightarrow k = \frac{2 . 5}{5} = 0 . 5\]
\[\text{ For y = 8 and k = 0 . 5, we have } : \]
\[x = ky\]
\[ \Rightarrow x = 8 \times 0 . 5 = 4\]
\[\text{ For y = 12 and k = 0 . 5, we have: } \]
\[x = ky\]
\[ \Rightarrow x = 12 \times 0 . 5 = 6\]
\[\text{ For x = 15 and k = 0 . 5, we have } : \]
\[x = ky\]
\[ \Rightarrow 15 = 0 . 5 \times y\]
\[ \Rightarrow y = \frac{15}{0 . 5} = 30\]

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Chapter 10: Direct and Inverse Variations - Exercise 10.1 [Page 6]

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RD Sharma Mathematics [English] Class 8
Chapter 10 Direct and Inverse Variations
Exercise 10.1 | Q 5.1 | Page 6

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