Two decimal places → denominator 100. So 0.45=10045. Divide top and bottom by 5: 10045=209.
Answer: A) 209
Key idea: Decimal ↔ fraction
**Decimal to fraction**: count the decimal places. Put the digits over 10, 100, 1000 accordingly. So 0.7 = 7/10. 0.43 = 43/100. 1.25 = 1 + 25/100 = 1 + 1/4 = 5/4.
**Fraction to decimal**: if the denominator is already 10, 100, 1000, …, just write the numerator with the right number of decimal places. 9/10 = 0.9. 27/100 = 0.27. For other fractions (e.g. 3/4), divide: 3 ÷ 4 = 0.75.
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