Subtract 90/81 from 20/75
1st number: 20/75, 2nd number: 1 9/81
20/75 - 90/81 is -38/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 81 is 2025
Next, find the equivalent fraction of both fractional numbers with denominator 2025 - For the 1st fraction, since 75 × 27 = 2025,
20/75 = 20 × 27/75 × 27 = 540/2025 - Likewise, for the 2nd fraction, since 81 × 25 = 2025,
90/81 = 90 × 25/81 × 25 = 2250/2025 - Subtract the two like fractions:
540/2025 - 2250/2025 = 540 - 2250/2025 = -1710/2025 - After reducing the fraction, the answer is -38/45
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