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Question
Complite the following table given that x varies directly as y .
| x | 5 | ... | 10 | 35 | 25 | ... |
| y | 8 | 12 | ... | ... | ... | 32 |
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Solution
\[\text{ Here, x and y vary directly } . \]
\[ \therefore x = ky\]
\[ x = 5 \text{ and } y = 8\]
\[i . e . , 5 = k \times 8\]
\[ \Rightarrow k = \frac{5}{8} = 0 . 625\]
\[\text { For y = 12 and k = 0 . 625, we have } : \]
\[x = ky\]
\[ \Rightarrow x = 12 \times 0 . 625 = 7 . 5\]
\[\text{ For x = 10 and k = 0 . 625, we have: } \]
\[x = ky\]
\[ \Rightarrow 10 = 0 . 625 \times y\]
\[ \Rightarrow y = \frac{10}{0 . 625} = 16\]
\[\text{ For x = 35 and k = 0 . 625, we have: } \]
\[x = ky\]
\[ \Rightarrow 35 = 0 . 625 \times y\]
\[ \Rightarrow y = \frac{35}{0 . 625} = 56\]
\[\text{ For x = 25 and k = 0 . 625, we have: } \]
\[x = ky\]
\[ \Rightarrow 25 = 0 . 625 \times y\]
\[ \Rightarrow y = \frac{25}{0 . 625} = 40\]
\[\text{ For y = 32 and k = 0 . 625, we have } : \]
\[x = ky\]
\[ \Rightarrow x = 0 . 625 \times 32 = 20\]
RELATED QUESTIONS
Which of the following quantities vary directly with each other?
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(ii) Weight of articles (x) and their cost (y).
(iii) Distance x and time y, speed remaining the same.
(iv) Wages (y) and number of hours (x) of work.
(v) Speed (x) and time (y) (distance covered remaining the same).
(vi) Area of a land (x) and its cost (y).
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