Subtract 21/8 from 81/7
1st number: 11 4/7, 2nd number: 2 5/8
81/7 - 21/8 is 501/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 8 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 7 × 8 = 56,
81/7 = 81 × 8/7 × 8 = 648/56 - Likewise, for the 2nd fraction, since 8 × 7 = 56,
21/8 = 21 × 7/8 × 7 = 147/56 - Subtract the two like fractions:
648/56 - 147/56 = 648 - 147/56 = 501/56 - In mixed form: 853/56
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