Subtract 81/5 from 2/21
1st number: 2/21, 2nd number: 16 1/5
2/21 - 81/5 is -1691/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
2/21 = 2 × 5/21 × 5 = 10/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
81/5 = 81 × 21/5 × 21 = 1701/105 - Subtract the two like fractions:
10/105 - 1701/105 = 10 - 1701/105 = -1691/105
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