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Question
Simplify:
(25 ÷ 28) × 2–7
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Solution
Using laws of exponents,
am ÷ an = (a)m – n and am × an = (a)m + n ...[∵ a is non-zero integer]
∴ (25 ÷ 28) × (2)–7 = (2)5 – 8 × (2)–7
= (2)–3 × (2)–7
= (2)–3 – 7
= (2)–10
= `1/2^10` ...`[∵ a^-m = 1/a^m]`
= `1/1024`
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| Position of Square on chess board |
Amount (in Rs) |
| 1st square | 1 |
| 2nd square | 2 |
| 3rd square | 4 |
