Subtract 21/81 from 20/25
20/25 - 21/81 is 73/135.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 81 is 2025
Next, find the equivalent fraction of both fractional numbers with denominator 2025 - For the 1st fraction, since 25 × 81 = 2025,
20/25 = 20 × 81/25 × 81 = 1620/2025 - Likewise, for the 2nd fraction, since 81 × 25 = 2025,
21/81 = 21 × 25/81 × 25 = 525/2025 - Subtract the two like fractions:
1620/2025 - 525/2025 = 1620 - 525/2025 = 1095/2025 - After reducing the fraction, the answer is 73/135
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