Subtract 90/81 from 15/25
1st number: 15/25, 2nd number: 1 9/81
15/25 - 90/81 is -23/45.
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,
15/25 = 15 × 81/25 × 81 = 1215/2025 - Likewise, for the 2nd fraction, since 81 × 25 = 2025,
90/81 = 90 × 25/81 × 25 = 2250/2025 - Subtract the two like fractions:
1215/2025 - 2250/2025 = 1215 - 2250/2025 = -1035/2025 - After reducing the fraction, the answer is -23/45
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