Subtract 8/45 from 81/21
1st number: 3 18/21, 2nd number: 8/45
81/21 - 8/45 is 1159/315.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
81/21 = 81 × 15/21 × 15 = 1215/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
8/45 = 8 × 7/45 × 7 = 56/315 - Subtract the two like fractions:
1215/315 - 56/315 = 1215 - 56/315 = 1159/315 - In mixed form: 3214/315
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