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Question
If a and b vary inversely to other, then find the values of p, q, r ; x, y, z and l, m, n.
| a | l | 9 | n | 6 |
| b | 5 | m | 25 | 10 |
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Solution
If a and b vary inversely to other.
i.e. ab = k ...(Constant)
For table,
| a | l | 9 | n | 6 |
| b | 5 | m | 25 | 10 |
If a = 6 and b = 1
Then, a × b = 6 × 10 = 60
⇒ k = 60
When a = l and b = 5, then
ab = k
⇒ l × 5 = 60
⇒ p = `60/5` = 12
When a = 9 and b = m, then
ab = k
∴ 9 × m = 60
⇒ m = `60/9 = 20/3`
When a = n and b = 25, then
ab = k
⇒ n × 25 = 60
⇒ r = `60/25 = 12/5`
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