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Question
If x varies directly as y, then
| x | 12 | 6 |
| y | 48 | – |
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Solution
If x varies directly as y, then
| x | 12 | 6 |
| y | 48 | 24 |
Explanation:
If x varies directly as y, then
`x/y = k` (constant) ...(i)
If x = 12 and y = 48, then
`x/y = 12/48 = 1/4`
⇒ `k = 1/4`
When x = 6, then from equation (i),
`6/y = k`
⇒ `6/y = 1/4` ...[Putting the value of k]
⇒ 6 × 4 = y × 1 ...[By cross-multiplication]
⇒ y = 24
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