Subtract 21/81 from 18/25
18/25 - 21/81 is 311/675.
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,
18/25 = 18 × 81/25 × 81 = 1458/2025 - Likewise, for the 2nd fraction, since 81 × 25 = 2025,
21/81 = 21 × 25/81 × 25 = 525/2025 - Subtract the two like fractions:
1458/2025 - 525/2025 = 1458 - 525/2025 = 933/2025 - After reducing the fraction, the answer is 311/675
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