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Question
On multiplying ______ by 2–5 we get 25.
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Solution
On multiplying 210 by 2–5 we get 25.
Explanation:
Let x be multiplied by 2–5 to get 25.
So, x × 2–5 = 25
⇒ `x xx 1/2^5 = 2^5` ...`[∵ a^-m = 1/a^m]`
∴ x = 25 × 25
= (2)5 + 5 ...[∵ am × an = (a)m + n]
= 210
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