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प्रश्न
If x varies directly as y, then
| x | 12 | 6 |
| y | 48 | – |
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उत्तर
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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संबंधित प्रश्न
In which of the following tables x and y vary directly?
(i)
| a | 7 | 9 | 13 | 21 | 25 |
| b | 21 | 27 | 39 | 63 | 75 |
(ii)
| a | 10 | 20 | 30 | 40 | 46 |
| b | 5 | 10 | 15 | 20 | 23 |
(iii)
| a | 2 | 3 | 4 | 5 | 6 |
| b | 6 | 9 | 12 | 17 | 20 |
(iv)
| a | 12 | 22 | 32 | 42 | 52 |
| b | 13 | 23 | 33 | 43 | 53 |
Complite the following table given that x varies directly as y .
| x | 6 | 8 | 10 | ... | 20 |
| y | 15 | 20 | ... | 40 | ... |
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| Mixture A | Mixture B |
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