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If logₖ(A) * log₅(k) = 3, then A is equal to (given k > 0, k not equal to 1).

1. 5k³
2. k³
3. 125
4. 243

Correct answer: 125

Solution

By the chain rule: logₖ(A) * log₅(k) = log₅(A). Setting this equal to 3 gives log₅(A) = 3, so A = 5³ = 125.

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