Subtract 80/9 from 81/21
1st number: 3 18/21, 2nd number: 8 8/9
81/21 - 80/9 is -317/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
81/21 = 81 × 3/21 × 3 = 243/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
80/9 = 80 × 7/9 × 7 = 560/63 - Subtract the two like fractions:
243/63 - 560/63 = 243 - 560/63 = -317/63
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