Subtract 81/18 from 21/25
1st number: 21/25, 2nd number: 4 9/18
21/25 - 81/18 is -183/50.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 18 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 25 × 18 = 450,
21/25 = 21 × 18/25 × 18 = 378/450 - Likewise, for the 2nd fraction, since 18 × 25 = 450,
81/18 = 81 × 25/18 × 25 = 2025/450 - Subtract the two like fractions:
378/450 - 2025/450 = 378 - 2025/450 = -1647/450 - After reducing the fraction, the answer is -183/50
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