When multiplying a decimal by a power of 10, the product can be found by shifting the decimal point to the right for positive powers of 10 and to the left for negative powers of 10.
For example:
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If you multiply by \(10^2\) (which is 100), you shift the decimal point two places to the right.
- \(2.5 \times 100 = 250\)
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If you multiply by \(10^{-1}\) (which is 0.1), you shift the decimal point one place to the left.
- \(2.5 \times 0.1 = 0.25\)
In summary, the general rule is:
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For a positive integer \(n\): \[ \text{Decimal} \times 10^n \quad \text{(shift the decimal point } n \text{ places to the right)} \]
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For a negative integer \(n\): \[ \text{Decimal} \times 10^n \quad \text{(shift the decimal point } |n| \text{ places to the left)} \]