Subtract 21/81 from 15/75
15/75 - 21/81 is -8/135.
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,
15/75 = 15 × 27/75 × 27 = 405/2025 - Likewise, for the 2nd fraction, since 81 × 25 = 2025,
21/81 = 21 × 25/81 × 25 = 525/2025 - Subtract the two like fractions:
405/2025 - 525/2025 = 405 - 525/2025 = -120/2025 - After reducing the fraction, the answer is -8/135
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