Subtract 81/28 from 21/14
1st number: 1 7/14, 2nd number: 2 25/28
21/14 - 81/28 is -39/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 14 and 28 is 28
Next, find the equivalent fraction of both fractional numbers with denominator 28 - For the 1st fraction, since 14 × 2 = 28,
21/14 = 21 × 2/14 × 2 = 42/28 - Likewise, for the 2nd fraction, since 28 × 1 = 28,
81/28 = 81 × 1/28 × 1 = 81/28 - Subtract the two like fractions:
42/28 - 81/28 = 42 - 81/28 = -39/28
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